• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.16-23
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• 2020

Water pipes are important facilities and consist of pipes of various specifications and materials. The annual average number of earthquakes in Korea is steadily increasing. Therefore, in case of the water pipe, it is estimated necessary to prepare for earthquakes. Damages to the water pipe by the earthquake can cause problems such as water supply and fire suppression, and cause damage to life and property. In Korea, however, it is difficult to find examples of seismic performance evaluation of water pipes based on experimental study. Damage to the water pipes by the earthquake is caused by the displacement-controlled behavior of the ground which is the liquifaction and fault lines. Especially, The damage to the water pipes by the earthquake is concentrated on the joint of the pipe. In particular, piping less than 200mm in diameter was found to be dangerous. Thus, in this study, the seismic and settlement performance of iPVC buried water pipes with fixed joints with a clamp of 150mm was evaluated with a test approach.

• Journal of the Korea Concrete Institute
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• v.24 no.2
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• pp.173-183
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• 2012

Recently, experimental studies to prevent explosive spalling based on spalling mechanism and addition of Polypropylene fiber in high strength concrete (HSC) are performed actively. However, with respect to ultra high strength concrete (UHSC), its compact internal structure is more difficult release vapor pressure at rapid rising temperature compared to HSC. Therefore, in this study, an experiment was conducted to evaluate spalling properties of UHSC using ${\Box}$ $100mm{\times}100{\times}H200mm$ rectangular specimen according to ISO-834 standard fire curve. With respect melting point of fiber, three fiber types of Polyethylene, Polypropylene, and Nylon fibers with melting temperature of $110^{\circ}C$, $165^{\circ}C$, and $225^{\circ}C$, respectively, were considered. Mixed fiber of 0.15% and 0.25% of concrete volume was used to consider spalling properties based on water vapor pressure release. Then, TGDTA test on fiber and FEM analysis were performed. The results showed that it is difficult to prevent initial spalling without loss of fiber mass even if fiber melting temperature is low. Also, in preventing thermal spalling, fiber that melts to rapidly create porosity within 10 minutes of fire is more effective than that of low melting temperature property of fiber.

• Journal of Korean Medical classics
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• v.11 no.2
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• pp.114-134
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• 1998

The conception of pyo(標) bon(本) joong(中) in the part of woongihak(運氣學) of negeong(內徑) one of the important thing that decides the relation between six gi(六氣) and samyum and samyang(三陰三陽) or between each other's of samyum and samyang itself, it says that the relation of Pyo-rce(表裏). So this conception from the ancient times have been used to explain the theory of meridian(經絡) and organs(五臟六腑) and in other important field of oriental medicine - Sanghannon(傷寒論), it became basis of explanation of pcthoiogical principles in the system of six kyung(六徑). At first, the subject or this study is limited to the rament of $\ll$Somun(素問)$\gg$ in order to find the accurate and original meanings of pyo(標) bon(本) joong(中). And the meanings are studied by the way of expanding it's meaning with basic conceptions of woongihak(運氣學) and astronomy included in negeong(內徑). In this study, the results are summarized as the followings. 1. The contents of - the 68th chapter of negeong(內徑), concerning pyo(標) and joong(中) come under chogi(初氣) and joonggi(中氣) of the same chapter, after consideration of astronomical knowledge. And they become active during the period that last about 30days, a haft of one step(一步) of kaekgi(客氣). 2. Bon(本) as a kind of six gi(六氣) that is revealed from internal principle of something, that is to say Ohhaeng(五行), comes mainly under the kaekgi(客氣) of woongihak(運氣學) with the meaning of 'sign' is thai the specific properties of six gi(六氣) are revealed to our sight, so we can feel that through the change of nature, Joong(中) is the other property hidden in the inside of six gi(六氣), that is a portion of original nature(本性) like the bon(本). 3. The relation of pyo(標) and bon(本) is like that bctween the principle hidden inside in all things(理) and it's expression into the real world(氣) also similar to thai of yumyang(陰陽) and ohhaeng(五行). Therefore bon(本), though it means one of the six gi(六氣), hale the property of ohhaeng(五行) and pyo(標) is revealed, with an appearance of samyum-samyang(三陰三陰). 4. pyo(標) and joong(中) are also the both sides of yum(陰) and yang(陰) that revealed under the change of yumyang-ohhaengl(陰陽五行) in the nature. For example, if the one is yang(陰), the other is yum(陰). In the process that the change of all things is revealed out, first the property of pyo(標) appears strongly and then that of joong(中) appears comparatively weakly. But, in spite of the inhibitive relation of yumyang(陰陽), pyo(標) and joong(中) promote each other. 5. Under the course of change. It happens according to the bon(本), the property of ohhaeng(五行) in the case of soyang(少陽) and taeyum(太陰), because the effect of moisture(濕) and fire(火) that makes hyung(形) and gi(氣) is very strong in the universe. In the case of taeyang(太陽) and soyum(少陰), it happens according to the bon(本) and pyo(標) because they hare the polarity of water and fire(火水), at the same time, are not separated each other. In the case of yangmeong(陽明) and gualyum(厥陰), the change appears only according to the joong(中), but not strongly because the phase of yangmeong(陽明) and gualyum(厥陰) is a lull phase processing to the next one.

• Journal of Digital Convergence
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• v.16 no.6
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• pp.197-204
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• 2018

The realistic Visual Effects using fluid simulation in 3D computer graphics are operated as important factors to improve the quality of images. The process of creating realistic motions of water, fire, explosion by controlling each property of fluid is called fluid simulation. In general, the creation of a fluid simulation concentrates on the main simulation work phase, however an effective method for initial set up is important for the main simulation work. The purpose of this study is to analyze the factors involved in the initial emission motion and shape of fluid and propose methods that can efficiently apply this into the initial set up. For the process of the research, first, problems are raised based on related researches, and second, two experiments, 'Dynamic Fluid Emitter Creation' and 'User Design Type Emission Velocity Solution', are conducted for more effective fluid simulation. Through this research, the effective fluid simulation of initial set up phase will be suggested through the user design-type emission control solutions.

• Journal of the Korean Wood Science and Technology
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• v.12 no.2
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• pp.20-26
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• 1984

This study was carried out to investigate the influence of chemical type and its retention in the fire-retardant treated plywoods on the static bending strength, a property peculiar to plywood. Being soaked in 20% aqueous solution of $(NH_4)_2SO_4$, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$. Borax-Boric acid and Minalith for 3 to 12 hours at three-hour intervals and redried at $120^{\circ}C$ in hot press, the treated plywoods were put to static bending test. The values of chemical treated plywoods in Stress at proportional limit, Modulus of elasticity, Modulus of rupture and Work per unit volume to proportional limit were widely higher than those of water treated plywoods(control) and Borax-Boric acid treatment showed the highest value in the four mechanical data. And the bending strength of fire-retardant treated plywoods increased with the extension of soaking time or the increase of chemical retention in themselves. Borix-Boric acid was the desirable fire-retardant for thin plywood in view of mechanical strength and soaking defects in this study.

• Korean Journal of Remote Sensing
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• v.38 no.6_3
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• pp.1749-1760
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• 2022

In modern society, human and social damages caused by natural disasters and frequent disaster accidents have been increased year by year. Prompt access to dangerous disaster sites that are inaccessible or inaccessible using state-of-the-art Earth observation equipment such as satellites, drones, and survey robots, and timely collection and analysis of meaningful disaster information. It can play an important role in protecting people's property and life throughout the entire disaster management cycle, such as responding to disaster sites and establishing mid-to long-term recovery plans. This special issue introduces the National Disaster Management Research Institute (NDMI)'s disaster management technology that utilizes various Earth observation platforms, such as mobile survey vehicles equipped with close-range disaster site survey sensors, drones, and survey robots, as well as satellite technology, which is a tool of remote earth observation. Major research achievements include detection of damage from water disasters using Google Earth Engine, mid- and long-term time series observation, detection of reservoir water bodies using Sentinel-1 Synthetic Aperture Radar (SAR) images and artificial intelligence, analysis of resident movement patterns in case of forest fire disasters, and data analysis of disaster safety research. Efficient integrated management and utilization plan research results are summarized. In addition, research results on scientific investigation activities on the causes of disasters using drones and survey robots during the investigation of inaccessible and dangerous disaster sites were described.

• Journal of Korean Academy of Nursing
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• v.27 no.1
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• pp.141-155
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• 1997

The universe has its order of yang and yin : all creation are continuously generated, grow and die, which is the results of the harmonious operation by yang and yin. Among all creation, the human is one of the samjae(three bases of the world, which are heaved earth, and man) and he is from the combined sukhi(a superior khi) of yang and yin. And human life itself is basically a condensed jonghyul (life blood) and at the same time it is only a transient joining of sadae(the four elements of earth, air, fire and water). Yang and yin, the two axes of the world, therefore. are the most crucial and fundamental concept to explain the generation and extinction of alt creation, to understand people in time and space. to find out the reality of human life as an organism, and, at last, to observe the state of human health. If so, what is the most essential idea in yang and yin\ulcorner It is taegeuk(chungkhi) or tao(of one yang and one yin). If the property of heaven and earth is kongon, taegeuk is a khi and tao a principle. And it can be said that a human body is merely a union of hyung and khi, that human life is an essence of sambo, jeongkhishin, that human health is a harmoninzed coordination of yang and yin because it is from the combined sukhi of yang and yin. Hyung. a vessel for sambo, jeongkhishin, is at the bottom and shin is on the top : the personality and the disposition of individuals differ according to their working. Thus. on the basis of the above discussion. the following can be offered as some suggestions for Korean Nursing Theory. Though human beings are part of Nature, they are the most eminent microcosm among all creation. So, as a subjet for nursing, a person should be understood with khijok kyoryu rather than with logical thinking, then mutual trust between the patient and the nurse can be established. The health of a person depends on the harmony of yang and yin. To be healthy, a person should consider harmonization with Nature(including his surroundings) as well as a balanced human relationships in society. Moreover, it is crucial for each person to obtain hoshim as a method of mind control rather than to only treat the symptoms of disease.

• Journal of Conservation Science
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• v.32 no.3
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• pp.425-436
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• 2016

The Yakhyeon catholic church (Historic Site No. 252 in Korea) that was constructed in 1892 has been the first western brick structure to ever have existed and one of the most important historical materials in the Korean modern architecture. After a fire had broken out at the catholic church in 1998, the stained glass on the back wall, the slab glass (dalle de verre) introduced by Lee Nam Guy in 1974, was repaired in 1999 because of singe scorch and water leakage. An analysis of the coloration elements showed that yellow, red and green included Zn, K and Cd, respectively. The glass of red contained Se, dark green contained Mn and Cr, and blue contained Pb and S. According to material analysis, the masonry joint was identified dolomite ($CaMg(CO_3)_2$) and calcite ($CaCO_3$), which was observed plate, columnar, rhombic and square of crystalline particles. Meanwhile, ultrasonic velocity in the stained glass recorded low speed in the middle and lower right of the window (an average of 4,130 m/s). And the joint was measured the lowest physical properties of the top left and middle of the window (an average of 2,053 m/s). This study have showed that extensive physical damage was founded to the left and middle rather than the right side. In this respect, more research in needed to conserve the correlation between color and physical properties.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.310-323
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• 1983

To study the effect of foaming agent on the production and property of light weight concrete, the tests of compressive, tensile, bending strengths and absorption rates of mortar were done under the different mixing ratio with J, A and D foaming agents. The results obtained were summarized as follows : 1. The strengths were decreased in richer mixing ratio and more addition of foaming agent. The decrease of strengths was the greatest at the level of 0.75% of foaming agent. The decreasing rate of strengths was in order of J, A and D foaming agent. 2. At the mixing ratio of 1:1, ${\sigma}_{28}$ and 0.75% of foaming agent, the compressive strength was decreased up to 34.9% by D, 47.8% by A and 86.8% by J foaming agent, respectively, the tensile strength was decreased up to 14.8% by D, 20.2% by A and 77.9% by J foaming agent, respectively, bending strength was decreased up to 19.9% by D, 35.0% by A and 79.1% by J foaming agent, respectively. The decrease of compressive strength was more severe than that of tensile and bending strengths. 3. The absorption rates were increased in poorer mixing ratio and more addition of foaming agent. The absorption rate was significantly higher at the early stage of immersed water. The absorption rate was in order of J, A and D foaming agent. 4. The decrease of strengths was inevitable in cement-mortar with foaming agent, but the cement mortar with foaming agent has such the properties of the light-weight, lnsulation, Keeping-warmth, sound proof and fire-proof that if could be utilized to the constructions which need low strengths.