• Journal of the Korean Ceramic Society
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• v.40 no.10
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• pp.1005-1014
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• 2003

This paper examines the hydration and physical properties of alkali-blast furnace slag cement activated by Na$_2$SiO$_3$, Na$_2$CO$_3$, NaOH, Na$_2$SO$_4$. Four levels of Na$_2$O content in mixtures, 1, 3, 5, and 7 wt%, were investigated, and a W/S ratio 0.5 was used to prepare paste and mortar specimens. Compressive strength measurement of mortars was carried out adding alkali activated slag 30 wt% to OPC. The main hydration products with alkali activator kinds were C-S-H,C$_4$AH$\_$13/, AFt and Al(OH)$_3$ etc. For using Na$_2$CO$_3$ activated slag, hydration ratio of slag was higher than that of different activators, and Na$_2$SO$_4$ activated slag mortar appeared the highest compressive strength values at 28 days with activator content of 5 and 7 wt%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.5
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• pp.269-275
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• 2014

In this study, chemical bath deposition method was used to grow Zinc sulfide(ZnS) thin films from $NH_3/SC(NH_2)_2/ZnSO_4$ solutions at $90^{\circ}C$. ZnS thin films have been prepared onto ITO glass. The concentrations of $ZnSO_4$ and $NH_3$ were varied while the concentration of Thiourea was fixed in 0.52 M. Structural, optical, electrical characteristic of ZnS thin films were measured. The physical and optical properties of different ZnS thin films were influenced severely by the concentration of the two reacting chemicals. The optimal concentration of $ZnSO_4$ and $NH_3$ was 0.085 M and 1.6 M, respectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.5
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• pp.129-138
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• 2004

Cherishing the dead is based in sadness. Designing a memorial space therefore has an inherent challenge to evoke the feeling that is so personal and varied by providing a physical space. The tendency of memorials, especially in the US after the mid 20th century, has been to emphasis each dead individual, as seen at the Vietnam Veterans Memorial in Washington, D. C., the Oklahoma City National Memorial in Oklahoma City, and so forth. In the process of designing the memorial of the Taiwanese Chi-chi earth-quake, Cheng Kim Park Robidoux tried to set up a series of spaces through which not only the relatives of the dead but also unrelated visitors could have their own spatial experiences, private rituals and public events, so that they can finally build up a collective memory. Sky-Well consists of a large bamboo forest enclosing a void. Without a particular entrance and guiding system, visitors stroll and get lost in the bamboo forest before they find the central void. The horror they experienced during the earthquake is melted down into the motion and phenomenology of the bamboo forest whereas the central void is reinterpreted as an empty mind, where people find solace from the sky. Details, such as the bamboo wall to place commemorative flowers and lotus blossom paving, are echoing the theme of rebirth.

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.103-109
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• 2005

In order to investigate the correlation of the physical chemical characteristics of Kimchi with its sourness and overall acceptability, the pH, the reducing sugar content, the total microbial counts and the lactic acid bacterial counts of Kimchi were examined during fermentation at $5^{\circ}C$, $10^{\circ}C$ and $20^{\circ}C$. In regard to pH, the pH of the fermentation at $10^{\circ}C$ and $20^{\circ}C$ was nearly in inverse proportion to the sourness, whereas the pH at $5^{\circ}C$ fermentation was in less than inverse proportion to the sourness. For the correlation of the reducing sugar and the sourness, sourness and the reducing sugar showed an inverse proportion until the acidity reached $0.8\%\~1.0\%$. The reducing sugar content at $10^{\circ}C$ and $20^{\circ}C$ was nearly similar for the highest overall acceptability, whereas the reducing sugar content at $5^{\circ}C$ was higher than the reducing sugar content at $10^{\circ}C$ and $20^{\circ}C$. In the case of the total microbial count, the total microbial count and the sourness of Kimchi fermented at $5^{\circ}C$did not show the highest values at the same point, but the highest values of the total microbial count and the sourness of Kimchi fermented at $10^{\circ}C$ and $20^{\circ}C$ were the same at a point. Also, at a point for the best overall acceptability, the total microbial count at $10^{\circ}C$ fermentation was the highest, whereas those at $5^{\circ}C$ and $20^{\circ}C$ fermentation were similar. In case of the lactic acid bacterial count, the lactic acid bacterial count and the sourness at $5^{\circ}C$ fermentation did not show the highest value at the same point, but that at $10^{\circ}C$ and $20^{\circ}C$ fermentation did. For the correlation of the physical chemical characteristics with sourness, the sourness of Kimchi fermented at $5^{\circ}C$ showed a very significant correlation with acidity and it also showed a positive correlation with pH and the total microbial count, but these were not significant differences($\alpha$=$0.5\%$). At $10^{\circ}C$ and $20^{\circ}C$ fermentation, the sourness showed very significant correlation with all the physical chemical characteristics.

• Korean Security Journal
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• no.27
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• pp.129-159
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• 2011

Physical security has always been an extremely important facet within the security arena. A comprehensive security plan consists of three components of physical security, personal security and information security. These elements are interrelated and may exist in varying degrees defending on the type of enterprise or facility being protected. The physical security component of a comprehensive security program is usually composed of policies and procedures, personal, barriers, equipment and records. Human beings kept restless struggle to preserve their and tribal lives. However, humans in prehistoric ages did not learn how to build strong house and how to fortify their residence, so they relied on their protection to the nature and use caves as protection and refuge in cold days. Through the history of man, human has been establishing various protection methods to protect himself and his tribe's life and assets. Physical security methods are set in the base of these security methods. Those caves that primitive men resided was rounded with rock wall except entrance, so safety was guaranteed especially by protection for tribes in all directions. The Great Wall of China that is considered as the longest building in the history was built over one hundred years from about B.C. 400 to prevent the invasion of northern tribes, but this wall enhanced its protection function to small invasions only, and Mongolian army captured the most part of China across this wall by about 1200 A.D. European lords in the Middle Ages built a moat by digging around of castle or reinforced around of the castle by making bascule bridge, and provided these protections to the resident and received agricultural products cultivated. Edwin Holmes of USA in 20 centuries started to provide innovative electric alarm service to the development of the security industry in USA. This is the first of today's electrical security system, and with developments, the security system that combined various electrical security system to the relevant facilities takes charging most parts of today's security market. Like above, humankind established various protection methods to keep life in the beginning and its development continues. Today, modern people installed CCTV to the most facilities all over the country to cope with various social pathological phenomenon and to protect life and assets, so daily life of people are protected and observed. Most of these physical security systems are installed to guarantee our safety but we pay all expenses for these also. Therefore, establishing effective physical security system is very important and urgent problem. On this study, it is suggested methods of establishing effective physical security system by using system integration on the principle of security design about effective security system's effective establishing method of physical security system that is increasing rapidly by needs of modern society.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.45.1-45.1
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• 2018

Formation of filaments and subsequent dense cores in ISM is one of the essential questions to address in star formation. To investigate this scenario in detail, we recently started a molecular line survey namely 'Filaments, the Universal Nursery of Stars (FUNS)' toward nearby filamentary clouds in Gould Belt using TRAO 14m single dish telescope equipped with a 16 multi-beam array. In the present work, we report the first look results of kinematics of a low mass star forming region L1478 of California molecular cloud. This region is found to be consisting of long filaments with a hub-filament structure. We performed On-The-Fly mapping observations covering ~1.1 square degree area of this region using C18O(1-0) as a low density tracer and 0.13 square degree area using N2H+(1-0) as a high density tracer, respectively. CS (2-1) and SO (32-21) were also used simultaneously to map ~290 square arcminute area of this region. We identified 10 filaments applying Dendrogram technique to C18O data-cube and 13 dense cores using FellWalker and N2H+ data set. Basic physical properties of filaments such as mass, length, width, velocity field, and velocity dispersion are derived. It is found that filaments in L~1478 are velocity coherent and supercritical. Especially the filaments which are highly supercritical are found to have dense cores detected in N2H+. Non-thermal velocity dispersions derived from C18O and N2H+ suggest that most of the dense cores are subsonic or transonic while the surrounding filaments are transonic or supersonic. We concluded that filaments in L~1478 are gravitationally unstable which might collapse to form dense cores and stars. We also suggest that formation mechanism can be different in individual filament depending on its morphology and environment.

• Journal of the Institute of Convergence Signal Processing
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• v.10 no.4
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• pp.274-279
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• 2009

The flow of a universal system-level design methodology consists of system specification, system-level hardware/software partitioning, co-design, co-verification using virtual or physical prototype, and system integration. In this paper, verification environments based-on SystemVerilog and SystemC, one is native-code co-verification environment which makes prompt functional verification possible and another is SystemVerilog layered testbench which makes clock-level verification possible, are implemented. In native-code co-verification, HW and SW parts of SoC are respectively designed with SystemVerilog and SystemC after HW/SW partitioning using SystemC, then the functional interaction between HW and SW parts is carried out as one simulation process. SystemVerilog layered testbench is a verification environment including corner case test of DUT through the randomly generated test-vector. We adopt SystemC to design a component of verification environment which has multiple inheritance, and we combine SystemC design unit with the SystemVerilog layered testbench using SystemVerilog DPI and ModelSim macro. As multiple inheritance is useful for creating class types that combine the properties of two or more class types, the design of verification environment adopting SystemC in this paper can increase the code reusability.

• Journal of Korean Society of Water Science and Technology
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• v.26 no.6
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• pp.61-72
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• 2018

In this study, applicability of the decentralized water supply system were investigated by the high flux evaluation using ceramic membrane with combined pretreatment process. A) filtration process increased the transmembrane pressure of 1.4 kPa and 89.5 kPa on 2 and $5m^3/m^2{\cdot}d$ of filtration flux, respectively, the physical backwashing recovery rate were less than 28.6%. The (B) Coag./Floc. - Sedi. combined process with 4 mg / L of A-PAC showed that the transmembrane pressure increased to within 6 kPa, the physical backwashing recovery rate was over 37.9 % higher than (A) Filtration process. (C) Coag./Floc. combined process showed an increase of transmembrane pressure compared with (B) Coag./Floc. - Sedi. combined process, physical backwashing recovery rate was over 84%. As a result of the membrane fouling analysis using the resistance in series model, the combined pretreatment process showed that the cake resistance (Rc) was more than 92% at membrane filtration flux of $2m^3/m^2{\cdot}d$. In the (C) Coag./Floc. combined process, cake resistance(Rc) was over 86% on high flux conditions. The coagulation floc contained in influent was removed by the membrane, and the cake layer formed with the removed floc was identified as reversible fouling resistance which could be recovered by physical backwashing. The decentralized water supply system, which has the limitation of site area and installation space, is considered to could be operation of high flux of ceramic membrane by applying (C) Coag./Floc. combined process without sedimentation process.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.4
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• pp.189-213
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• 1980

1. Aiming at supply of basic informations on tree species siting and forest fertilization by understanding of soil properties that are demanded by each tree species through studies of forest soil's morphological, physical and chemical properties in relation to tree growth in our country, the necessary data have been collected in the last 10 years, are quantified according to quantification theory and are analyzed in accordance with multi-variate analysis. 2. Test species, larch and the Korean white pine, are plantable in extensive areas from mid to north in the temperate zone and are the two most recommended reforestation tree species in Korea. However, their respective site demands are not known and they have been in confusion or considered demanding the same site during reforestation. When the Korean white pine is planted in larch sites, it has shown relatively good growth. But, when larch is planted in the Korean white pine site it can be hardly said that the larch growth is good. To understand on such a difference soil factors have been studied so as to see how the soil's morphological, physical and chemical factors affect tree growth helped with the electronic computer. 3. All the stands examined are man-made mature forests. From 294 larch plots and 259 white pine plots dominant trees are cut as samples and through stem analysis site index is determined. For each site index soil profiles are made in the related forest-land for analysis. Soil samples are taken from each profile horizon and forest-land productivity classification tables are worked out through physical and chemical analysis of the soil samples for each tree species for the study of relationships between physical, chemical and the combined physical/chemical properties of soil and tree growth. 4. In the study of relationships between physical properties of soil and tree growth it is found out that larch growth is influenced by the following factors in the order of deposit form, soil depth, soil moisture, altitude, relief, soil type, depth of A-horizon, soil consistency content of organic matter soil texture bed rock gravel content aspect and slope. For the Korean white pine the influencing factors' order is soil type, soil consistency bed rock aspect depth of A-horizon soil moisture altitude relief deposit form soil depth soil texture gravel content and slope. 5. In the study of relationships between chemical properties of soil and tree growth it is found out that larch growth is influenced by the following factors in the order of base saturation organic matter CaO C/N ratio, effective $P_2O_5$ PH.exchangeable $K_2O$ T-N MgO C E C Total Base and Na. For the Korean white pine the influencing factors' order is effective $P_2O_5$ Total Base T-N Na C/N ratio PH CaO base saturation organic matter exchangeable $K_2O$ C E C and MgO. 6. In the study of relationships between the combined physical and chemical properties of soil and tree growth it is found out that larch growth is influenced by the following factors in the order of soil depth deposit form soil moisture PH relief soil type altitude T-N soil consistency effective $P_2O_5$ soil texture depth of A-horizon Total Base exchangeable $K_2O$ and base saturation. For the Korean white pine the influencing factors' order is soil type soil consistency aspect effective $P_2O_5$ depth of A-horizon exchangeable $K_2O$ soil moisture Total Base altitude soil depth base saturation relief T-N C/N ratio and deposit from. 7. In the multiple regression of forest soil's physical properties larch's correlation coefficient is 0.9272 and for the Korean white pine it is 0.8996. With chemical properties larch has 0.7474 and the Korean white pine has 0.7365. So, the soil's physical properties are found out more closely related with tree growth than chemical properties. However, this seems due to inadequate expression of soil's chemical factors and it is proved that the chemical properties are not less important than the physical properties. In the multiple regression of the combined physical and chemical properties consisting of important morphological and physical factors as well as chemical factors of forest soils larch's multiple correlation coefficient is found out to be 0.9434 and for the Korean white pine it is 0.9103 leading to the highest correlation. 8. As shown in the partial correlation coefficients larch needs deeper soil depth than the Korean white pine and in the deposit form colluvial and creeping soils are demanded by the larch. Adequately moist to too moist should be soil moisture and PH should be from 5.5 to 6.1 for the larch. Demands of T-N soil texture and soil nutrients are higher for the larch than the Korean white pine. Thus, soil depth, deposit form, relief soil moisture PH N altitude and soil texture are good indicators for species sitings with larch and the Korean white pine while soil type and soil consistency are indicative only limitedly of species sitings due to their wide variation as plantation environments. For larch siting soil depth deposit form relief soil moisture PH soil type N and soil texture are indicators of good growth and for Korean white pine they are soil type soil consistency effective $P_2O_5$ and exchangeable $K_2O$, which is demanded more by the Korean white pine than larch generally. 9. Physical properties of soil has been known as affecting tree growth to greatest extent so far. However, as a result of this study it is proved through computer analysis that chemical properties of soil are not less important factors for tree growth than chemical properties and site demands for larch and the Korean white pine that have been uncertain So far could be clarified.

• Journal of Korean Physical Therapy Science
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• v.24 no.2
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• pp.45-52
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• 2017

Purpose : Most of the moderns have been spent sedentary life style in front of desk or on the chairs, so that their hamstring muscles are shorted commonly and the shortness of hamstring muscles are caused to some problems in functional activities. The purpose of this study was to compare the effectiveness of thermotherapy with hot-pack and ultrasound on the tightness of hamstring muscles in individuals with hamstring tightness. Method : Twenty-eight persons with hamstring tightness participated in this study. They were randomly assigned to three exercise groups: stretching group(n=10), hot-pack group(n=9), and ultrasound group(n=9). Before experiment, this study measured the angle of hip flexion using a inclinometer in all participants. Stretching group conducted actively stretching on their shorted leg for 30 seconds, 3 times, and rest for 10 seconds between each exercises. Hot-pack group have applied hot-pack($70{\sim}75^{\circ}C$) on shorted hamstring muscles for 20 minutes before stretching exercise. Ultrasound group have applied therapeutic ultrasound(1 MHz and 1.5W/cm2) on shorted hamstring muscles for 10 minutes before stretching exercise. All data was analysed using one-way repeated ANOVA. Result : The results revealed that ultrasound therapy before stretching is more effective to the flexibility on hamstring muscles than hot-pack before stretching and stretching only. Conclusion : The results of this study show that thermotherapy with therapeutic ultrasound will be effective on the shortness of hamstring muscles before stretching exercise.