• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.72-77
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• 2005

This study was performed to examine the effects of aluminum addition and recycle of NaOH waste solution on CEC and crystallinity of zeolite synthesized from fly ash. The added aluminum was used as the source of zeolite framework in zeolitization of fly ash. CEC and crystallinity of Na-P1 zeolite synthesized with aluminum addition were increased from 285 to $365cmol_c\;kg^{-1}$ and from 44.3 to 57.1% compared to that of simple hydrothermal treatment, respectively. The recycled NaOH solution did not affect the CEC of reaction products, though the crystallinity was decreased a little. Therefore, the additional supply of aluminum could improve the quality of zeolite synthesized from fly ash and the recycle of NaOH during zeolite synthesis can save the chemical without any adverse effects in the quality of synthesized seolite.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.43-50
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• 2007

Veterinary antibiotics have been widely used to increase feed efficiency, to prevent disease, and to promote growth as well as to control disease. The antibiotics administered can be excreted through the urine and feces. One of the major routes of veterinary antibiotics entering soil and water environment is via the application of animal manure to agricultural land as an organic fertilizer source. Since little is known about impacts of antibiotics on the environment, this study was conducted to prioritize the veterinary antibiotics based on the consumption and potential to reach the environment. Among 83 veterinary antibiotics consumed in Korea, ten antibiotics were used at the greater dose than 25 Mg in 2004. Potential to reach the environment was determined according to excretion rate after administered to animals and sorption affinity to soil solids after applied to agricultural land. Seventeen antibiotic active ingredients (Ais) were classified as 'High' priority in terms of the potential to reach the environment. An overall priority score was determined by combining priority score based on consumption with the degree of potential environment exposure. Twenty veterinary antibiotic AIs were classified as 'Very high' or 'High' priority requiring detailed assessment. The antibiotic AIs were identified four aminoglycosides, two macrolides, two penicillins, five sulfonamides, three tetracyclines, two quinolones, and two miscellaneous. Eight veterinary antibiotic AIs including amoxicillin, carbadox, chlortetracycline, neomycin, oxytetracycline, sulfamethazine, sulfathiazole, and tylosin were identified to have a greater priority of environmental risk in Korea.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.5
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• pp.901-909
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• 2021

Since mobile devices have limited computational resources, it tends to use the cloud to compute or store data. As real-time becomes more important due to 5G, many studies have been conducted on edge clouds that computes at locations closer to users than central clouds. The farther the user's physical distance from the edge cloud connected to base station is, the slower the network transmits. So applications should be migrated and re-run to nearby edge cloud for smooth service use. We run applications in docker containers, which is independent of the host operating system and has a relatively light images size compared to the virtual machine. Existing migration studies have been experimented by using network simulators. It uses fixed values, so it is different from the results in the real-world environment. In addition, the method of migrating images through shared storage was used, which poses a risk of packet content exposure. In this paper, Containers are migrated with Secure CoPy(SCP) method, a data encryption transmission, by establishing an edge computing environment in a real-world environment. It compares migration time with Network File System, one of the shared storage methods, and analyzes network packets to verify safety.

• Journal of Korean Home Economics Education Association
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• v.33 no.1
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• pp.37-62
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• 2021

The purpose of this study is to develop a project-based teaching-learning instruction to solve the problems in family life. The developed process can be a practical plan to activate environmental education centered on living environment problems curriculum of Home Economic Education[HEE]. In order to achieve the purpose of this study, the curriculum of HEE and environmental education categories were compared and analyzed. The study selected 10 themes and developed a project-based HEE teaching-learning instruction with 8 sessions. The characteristics of the developed teaching-learning instruction are as follows. First, HEE curriculum included environmental knowledge, values and attitudes, competence, and practice and participation in environmental education and related categories in achievement standards and learning elements. Second, since HEE curriculum has a teaching-learning instruction plan based on project-based learning that allows learners to recognize and solve problems themselves was developed based on the real life-centered learning themes related to environmental education. It was also proposed that the subject of HEE has a high correlation with environmental competence and environmental practice, and thus environmental contents that can raise students' interests in society and environment should be added to the HEE curriculum. The teaching-learning instruction developed in this study can be used for classes such as HEE classes or free semeste. A follow up study would need to test the educational effects of this teaching and learning plan by implementing it to the actual class.

• Korea Science and Art Forum
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• v.37 no.2
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• pp.275-292
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• 2019

This study was initiated with the attention of demanding new and diverse approaches, we're talking familiar with imitations in the design process like a way to draw a image. So I studied a convergence of humanities and visual arts with the understanding and conceptual approach of the formless. The purpose of this study is to develop formless languages and to organize practical courses which are to enable deeper research and design expression on theoretical approaches and explanations of outcomes required before and after the process when we practice in connection with the formless. The method of this study is to draw detailed items from selected words through advanced researches, work and author researches and practice teaching. The results of the study I proposed the formless language that is related to the horizontality in spatial positioning system, and pulse in the separation of space and time, and entropy in structural orders of the system, and base materialism in the limitation of matter as the operating mechanism and parent item of formless. And those elements are related with shape, size, shading, color, texture, space, structure as visual elements of formative elements and those have various adjectival meanings as the subordinate concept. So I presented an education materials of basic design which is to enable understanding and expressing the formless language in the overall process of formless visual art(theoretical approach, practice course, presentation, etc.). Based on these study results, I hope that this educational materials will be used as educational contents that makes them express and understand different new beauties, and a role that reveals social identity, and a reference for research on a formless visual arts.

• Food Engineering Progress
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• v.14 no.4
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• pp.328-334
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• 2010

Recently the enhancement and development of makgeolli processing to extend shelf life are constantly accomplished. However, the standardization to restrict microorganisms including cold chain system and sterilizing system has not been established yet. Therefore, the objective of this study was to investigate the storage stability of makgeolli using quick freezing (QF) and slow freezing (SF) storage methods. The storage period was 40 days. Every 10 days, the samples were taken from the quick and slow freezing storage chamber. And then the samples were put into a $10^{\circ}C$ refrigerator for 24 hr to thaw them. The final samples were evaluated for chemical experiments and microbial cell counts. As a result, reducing sugar content was dramatically increased after 10 days for all of the samples. In titratable acidity and color values case, these values did not significantly change by storage time. In case of lactic acid bacteria and yeasts for all the samples, there was a decreasing tendency with storage time. Especially, in case of lactic acid bacteria, the changes from the beginning microbial cell counts ($4.1{\times}10^7$ CFU/mL) for QF and SF after 20 days were $3.6{\times}10^6$ CFU/mL and $1.8{\times}10^4$ CFU/mL, respectively. This result showed that the freezing methods could restrict the microbial growth in makgeolli.

• Journal of Wetlands Research
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• v.21 no.1
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• pp.43-56
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• 2019

Irrigated and flooded rice paddy contributes to the greenhouse gas emissions (GHG) that affect climate. This in turn affects the supply and reliability of the water needed for rice production. This dynamic makes current rice production methods foreseeably less sustainable over time while having other undesirable effects. Intermittent irrigation by a means of the system of rice intensification (SRI) and alternate wetting and drying (AWD) methods was reviewed to reduce global warming potential (GWP) from 29% to 90% depending on site-specific characteristics from flooded rice paddy and analyzed to be a promising option for enhancing the productivity of water as well, an increasingly constraining resource. Additional benefits associated with the SRI/AWD can be less arsenic in the grain and less degradation of water quality in the run-off from rice paddies. Adoption and expansion of intermittent irrigation of SRI/AWD may require costly public and private investments in irrigation infrastructure that can precisely make irrigation control, and the involvement and upgrading of water management agencies and farmer organizations to enhance management capabilities. Private and public collaboration as a means of earning carbon credit under the clean-development mechanism (CDM) with SRI/AWD for industries to meet as a part of their GHG emission quota as well as a social contribution and publicity program could contribute to adopt intermittent irrigation and rural investment and development. Also, inclusion of SRI and AWD in programs designed under CDM and/or in official development assistance (ODA) projects could contribute to climate-change mitigation and help to achieve UN sustainable development goals (SDGs).

• Journal of the Korea Institute of Construction Safety
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• v.2 no.1
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• pp.36-44
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• 2019

$21^{st}$ century is digitally civilized era. Technologies such as AI, Iot, Big Data, Mobile and etc makes this era digitally advanced. These advancement of the technology greatly impacted detection range of the radar. Human's eye sight can see about 20Km and hear 20 ~ 20000 Hz. These limitations can be overcome using radar. This radar technology is used in military, aircraft, ship, vehicle and etc. to replace human eye. However, radar technology is capable of making False Alarm Rate. This document will propose the fix of these problems. Radar's distortion includes beam refraction, diffraction and reflection. These inaccurate data result in deterioration of human judgements and my cause various casualties and damages. Radar goes through annual testing to test how many false alarm is being produced. Normal radar usually makes 10 to 20 False alarms. In emergency situation, if operator were to follow this false alarm, this might result in following false object or take 12 more seconds to follow the right object. This problem can be overcome by using different radar data from different places and angles. This helps reduces False Alarm rate and track the object twice as fast.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.28-34
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• 2019

Solar energy is one of the most abundant renewable energy sources on Earth but there are restrictions on the use of solar thermal energy due to the time-discrepancy between the solar-rich season and heating demand. In Europe and Canada, a seasonal solar thermal energy storage (SSTES), which stores the abundant solar heat in the summer and uses the heat for the winter heating load, is used. Recently, SSTES has been introduced in Korea and empirical studies are actively underway. In this study, a $2,000m^2$ flat plate type solar collector and $20,000m^2$ of borehole thermal energy storage (BTES) were studied for a greenhouse in Hwaseong City, which has a heating load of 2,164 GJ/year. To predict the dynamic performance of the system over time, it was simulated using the TRNSYS 18 program, and the solar fraction of the system with the control conditions was investigated. As a result, the solar BTES system proposed in this study showed an average solar fraction of approximately 60% for 5 years when differential temperature control was applied to both collecting solar thermal energy and discharging BTES. The proposed system simplified the configuration and control method of the solar BTES system and secured its performance.

• 한국노년학
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• v.37 no.3
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• pp.669-686
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• 2017

The purpose of this study is to investigate types of neighborhood environments and to verify whether the types of neighborhood environments are directly related to life satisfaction of older adults. To achieve this goal, I used'2014 National Survey on Older Koreans' data which surveyed the older adults aged 65 and over living in the community and a total of 10,281 respondents were analyzed. To determine the types of neighborhood environment, the time taken by walking from community organizations or places such as grocery stores, medical centers, administrative agencies, welfare centers, public transportation was used as an neighborhood environment indicators. As a results, there were six types of neighborhood environment: a leisure-welfare walk-limited type(20.3%), a leisure-welfare long-distance type(15.5%), a balanced proximity type(7.8%), a store-traffic type(35.8%), a traffic proximity type(10.1%), and a marginalized area type(11.3%). Compared to the balanced proximity type, older adults living in a store-traffic type and a marginalized area type were more likely to have negative life satisfaction. older adults who have higher life satisfaction were more likely to be female, more educated, get higher household income, and have a spouses or partner. Moreover, the better the health conditions, the higher the frequency of contact with children, siblings, friends and neighbors, the higher the satisfaction of life. Finding from the study highlight the importance of neighborhood environment in late life and provide implications for building age-friendly community.