• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.2
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• pp.33-41
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• 2018

Large amounts of leaves from street trees fall onto the streets annually and need to be cleaned and treated. Cherry trees are common street trees in Korea. The adsorption characteristics of Pb(II) by cherry leaf (CL) and cherry leaf-derived biochar (CB) were studied through a series of batch experiments. CB was produced through the carbonization of CL at $800^{\circ}C$ for 90 min. Carbonization increased the C content and pH value, while decreased H and O contents. Well developed pore structure was observed at the surface of CB. The pseudo-second order model better described the kinetics of Pb(II) adsorption onto CL and CB, indicating that the rate-limiting step of the heavy metal sorption is chemical sorption. Fast adsorption rates and high adsorption capacities were obtained by the carbonization from CL to CB. Langmuir models better adequately described the Pb(II) adsorption onto CL and CB. Maximum adsorption capacities of Pb(II) expressed by Langmuir constant, $Q^0$ were 37.31 mg/g and 94.34 mg/g, when CL and CB were used as adsorbents, respectively.

• Journal of Soil and Groundwater Environment
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• v.6 no.4
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• pp.25-40
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• 2001

In order to investigate the degree of heavy metal pollution, 280 urban gully-pot sediments were collected from 13 localities in eastern part of Seoul. The uncontaminated stream sediments were also studied for comparison. A series of studies have carried out concerning the physicochemical characteristics of the sediments and the distribution of Cd, Co, Cr, Cu, Ni, Pb, and Zn. Total metal concentrations of gully-pot sediments and uncontaminated stream sediments were analyzed using acid extraction. After predigestion with $NHO_3$, the sample was digested with mixed acid ($NHO_3$-$HClO_4$). The gully-pot sediments were characterized by very high concentrations of Zn, Cu, Pb and Cr, indicating an anthropogenic contribution of these metals to the sediment chemistry Heavy metal concentrations in the gully-pot sediments were 1-329 times higher than the mean content of metals in the uncontaminated stream sediments, depending on the metals. In particular, the highest mean concentrations of Zn, Cu, Pb and Cr were noticed in the gully-pot sediments from Yeouido, Junggu, Junggu, and Dongdaemungu, respectively. The mean value of total Zn concentration in the business and commercial areas is 2-3.5 times higher than that in industrial areas. This suggests that Zn is mainly derived from automobiles (rubber of automobile tires). The mean concentrations of Cu and Cr are significantly high in the commercial and industrial areas, indicating that industrial activities may cause the accumulation of Cu and Cr in the sediments. The Pb level in gully-pot sediments is comparatively low, due to the use of unleaded gasoline in automobiles since 1987.

• 대한공업교육학회지
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• v.45 no.2
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• pp.1-20
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• 2020

The purpose of this study is to develop an assembly-type liquid level control experimental equipment and a hands-on activity task that can be applied to the class so that students studying the chemical industry can easily understand the liquid level control. For this purpose, the content elements related to liquid level control in the chemical industry practice course of the 2015 revised curriculum was analyzed, a hands-on activity task with an assembly-type liquid level control experimental equipment was and developed. And then, expert verification was also performed and the hands-on activity task was applied to 19 students of S meister high school. The results obtained through this are as follows. First, the existing completion-type liquid level control experimental equipment was explored, and based on this, a new assembly-type liquid level control experimental equipment that can be assembled by students and used for practices was designed and manufactured. Second. by analyzing the contents of the NCS-based 'Chemical Process Maintenance Operation' practical course of the 2015 revised curriculum, learning contents related to level control were extracted. Among the contents related to the level control, the practice with understanding the process flow chart, manufacturing the level control experimental equipment, measuring the flow rate, and checking the level control phenomenon were conducted with the assembly-type liquid level control experimental equipment to systematically learn the level control.

• Korean Journal of Community Nutrition
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• v.18 no.4
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• pp.386-401
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• 2013

This study was conducted to analyze traditional aspects of school lunch menus in Korea. We conducted a content analysis of menu-related contents included in guidelines for school lunch programs provided by 16 city and provincial education offices. In addition, the data of 10,495 menus for the third week of December 2010 and March, July, October 2011 from 557 elementary, middle, and high school were analyzed by school grade, area, and province. The results showed that there were no specific and detailed guidelines for menu planning in terms of traditional food culture in most of the guidelines for school lunch programs. However, the basic traditional menu composition was maintained in school lunch menus. The percentage of menus including rice and Kimchi was 97% and 95%, respectively, and that including Korean soup was about 72%. However, the frequency of serving Namul, Korean seasoned vegetable dish, accounted for only about 52% of the menus. The percentage of the menus following the traditional food group pattern including such five food groups as rice, Korean soup, Kimchi, Namul, and optional Korean side dish was only about 35%. The percentage of the menus following the traditional food group pattern excluding Namul from the five food groups accounted for about 30%. The traditional food group score, calculated by allocating 1 point to each of the five food groups was 4.06 out of 5 points on average. Elementary schools and schools in rural area and in Jeolla-do province served traditional menus more frequently. In conclusion, school lunch programs need to consider establishing traditional foods-based standards and relevant guidelines for school lunch, particularly for high schools and schools in urban areas and in some provinces.

• Hwankyungkyoyuk
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• v.9 no.1
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• pp.39-57
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• 1996

All kinds of environmental problems are related to each local and geographical environment. For this reason, it is necessary for schools in each region to provide environmental education which suits the geographical character of their particular region. In order to provide solutions to the environmental problems of each school's geographic region, the goal of this research is as follows: 1. We can make students realize the relationship between the human race and the environment by teaching according to the environmental conditions in each local area. 2. By teaching students about the problems in their own local environment, we can increase their concern about the state of their local surroundings. 3. When teaching about the environment, it is useful to use educational material which suits the character of each local region. 4. Students' interest in environmental preservation can be aroused through extracurricular environmental activities. The ares concerned are Chonnam and Kwangju City, which are divided into urban, industrial, rural, coastal, and mountainous areas. The conclusion about considering environmental education in environmental school social studies is as follows: 1. Kwangju and Chonnam should be divided into five sections, each with similar geographical environments. This will be an improvement over the old uniform approach to environmental studies in which all regions were treated as being the same each region will now receive special attention. 2. It is necessary to maximize the efficient use of the Environmental Education Building. When Media, environmental data and special materials for environmental education are used effectively, teachers can lead class effectively and students will be more interested in the class. 3. We can detect the cause of pollution, increase interest in the environment and easily solve environmental problems by collecting and displaying environmental educational materials. 4. An environmental education corner could boost students' interest in environmental problems and could act as a kind of bridge between theoretical and practical education. 5. Media and environmental data must be specialized according to the geographic character of each region. In this way, we can expect to improve the quality of environmental education over the simplistic environmental education of previous years. 6. Students will become interested in the problems of the region in which they live through social studies, and primarily through the environmental curriculum. 7. We can prevent learning deficiencies by making a consistent teaching plan. The teaching and learning methods will be improved and the teachers will be proud of what they teach. 8. The purpose of the Education Procedure Content Analysis is to make teaching and learning concise and easy by systematizing environmental and related subjects. This can be done by adding an environmental unit to the geographic section of social studies. 9. Citizens' interest in their own residential environment can be increased through action by sustaining environmental preservation movements to local region people.

• Journal of the Korea Concrete Institute
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• v.27 no.3
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• pp.291-298
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• 2015

In this paper, a bundled diagonal reinforcement using high performance steel fiber was proposed to enhance the construct ability and seismic performance. Experiments of coupling beam was composed of four specimens and the hysteretic behavior evaluated for reverse cyclic loading to specimens using high performance steel fiber. The main variables of the experiment is a amount of stirrup and bundled reinforcement, depending on whether the mix of steel fiber. Specimen which criteria was applied 100% of stirrup and bundled diagonal reinforcement of ACI318 criteria. With this, by appling same diagonal reinforcement, two specimens were created by adjusting stirrup of 75%, 50%. So, a total of four specimens were produced. When coupling beam was placed concrete, this experiment was mixed in a content of steel fiber 1%. All the specimens were produced by aspect ratio 3.5(l/h=1050/300) to a half-scale. In this result, two specimens as reduced to stirrup of 75%, 50% was no significant difference in the strength, stiffness and energy dissipation capacity, respectively compared to the stirrup of 100%.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.415-422
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• 2013

The contents development for the Internet and cyber tour has been attempted in a number of areas. 3D topography of the spatial environment, land planning and land information contents as a 3D tour of the future ubiquitous city safe for tourism due to the implementation of information made available major area. Domestic service, and in urban areas of the country where land and precise spatial information in order to shoot satellites and aircraft in the area you want to mount the camera on a variety of photo images taken by conducting 3D spatial that is required is able to obtain the information. Geo spatial information in a variety of direct or indirect acquisition of the initial spatial data into a database for accurate collection, storage, editing, manipulation and application technology changes in the future by establishing a database of 3D spatial by securing content organization ubiquitous tourist to take advantage of new tourism industry was greatly. As a result of this study for future tourism using geo spatial information and analysis of 3D modeling by intelligent land information indirectly, with quite a few stereo site experience and a variety of tourist spatial acquisition and utilization of information could prove.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.4
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• pp.45-53
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• 2010

This paper has attempted to propose a more progressive direction for U-environmental sculptures in a ubiquitous urban space in terms of usability, service, function and formative characteristics that enhance user satisfaction with these sculptures. For this, Media Pole, a U-environmental sculpture on Gangnam U-Street, has been examined. The results of this study are as follows: First, a study of user satisfaction was planned after establishing levels of satisfaction in terms of service, function and formative characteristics. In terms of satisfaction by the section of Media Pole, the public transportation map was the most influential in service while street culture and beauty of shape were critical in function and formative characteristics, respectively. In the relationship between satisfaction by section and overall satisfaction, furthermore, functional satisfaction had the biggest influence. Therefore, the development of human-centered functional factors which have pleasant and touching stories to facilitate communication with citizens are important in order to develop various Media Pole contents to enhance user satisfaction with the U-environmental sculpture and allow it evolve into a Gangnam landmark Since we are in the initial stage of a U-city, there are many problems that need to be addressed such as a lack of natural beauty, poor material quality of environmental sculptures, absence of storytelling, poor technology, lack of content, poor profitability and lack of means of social communication. In the end, the development of a comfortable, people-friendly space and U-environmental sculptures are needed in consideration of economic, social and cultural aspects instead of focusing on advanced technology only.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.1
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• pp.81-88
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• 2009

This study has shown the tendency to enhance Sand Flux, a device of separating screening the foreign matter, for the recycling of construction waste possible to improve the quality of wet type production system meaningfully as part of research. As a result of experiment on the basic material properties, this study had a tendency to improve the quality and performance significantly in case of absolute surface dried density, 0.08mm sieve throughput, volume of clay lumps, and content of organic foreign matter. In addition, as a result of examining the quality characteristics of mortar, this study has shown the tendency that the flow and compressive strength more increased than the mortar using RS-II by utilizing RS-VI recycled sand produced finally through the device Sand Flux. As for the shrinkage properties, this study has shown the character the generation rate of crack of mortar using RS-IV recycled sand produced finally through the device Sand Flux.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.2
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• pp.106-117
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• 2006

We measured the concentrations of organic matter and metallic elements (Al, Fe, Cr, Mn, Ni, Cu, Zn, As, Cd, Pb and Hg) in the surface sediments of Masan Harbor (in the southern sea, Korea) to evaluate the geochemical characters of sediment and the pollutions by organic matter and metallic elements. The mean grain size of the surface sediments in the study area ranged from $5.6{\phi}$ to $7.8{\phi}$, indicating silt sediment. The water content of the surface sediments exceeded 60% except at some stations. The contents of ignition loss (IL), total organic carbon (TOC) and total nitrogen (TN) ranged from 7.2-14.3%, 1.2-3.2%, and 0.10-0.28%, respectively. Based on the C/N ratios, the organic matter in the surface sediments of Masan Harbor may originate from terrigenous sources including fluvial inputs (mainly sewage in urban areas). The chemical oxygen demand (COD) and acid volatile sulfide (AVS) ranged from $11.3-29.9\;mgO_2/g\;dry$ and 0.20-4.47 mgS/g dry, respectively, and low concentrations were observed near a shipping route. In addition, the concentrations of metallic elements showed large spatial variations in Masan Harbor and the distributions of metallic elements were also comparable to those of organic matter. This implies that the distributions of organic matter and metallic elements in the surface sediments of Masan Harbor are mainly controlled by biogenic matter and artificial action (mainly dredging). In addition, we calculated the enrichment facto. (EF) and geoaccumulation index (Igeo) in order to evaluate pollution by metallic elements. The enrichment of metallic elements relative to Al was three to eighteen times higher at the study sites, compared to levels in the Earth's crust except for Fe, Ni and Mn. In addition, the Igeo class indicated that the surface sediments in the study area were moderately to strongly polluted in terms of metallic elements.