• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.824-829
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• 2011

In recent years, there has been an increasing public concern about fecal contamination of water, air and agricultural produce by pathogens residing in organic fertilizers such as manure, compost and agricultural by-products. Efforts are now being made to control or eliminate the pathogen populations at on-farm level. Development of efficient on-farm strategies to mitigate the potential risk posed by the pathogens requires data about how the pathogens prevail in livestock manure composts and organic fertilizers. Microbiological analysis of livestock manure composts and organic fertilizers obtained from 32 and 28 companies, respectively, were conducted to determine the total aerobic bacteria count, coliforms, Escherichia coli count and the prevalence of Staphylococcus aureus, Bacillus cereus, Salmonella spp., Escherichia coli O157:H7, Listeria monocytogenes, and Cronobacter sakazakii. The total aerobic bacteria counts in the livestock manure composts and organic fertilizers were in the range of 7 to $9log\;CFU\;g^{-1}$ and 4 to $6log\;CFU\;g^{-1}$, respectively. In the livestock manure composts, coliforms and E. coli were detected in samples obtained from 4 and 2 companies, respectively, in the range of 2 to $5log\;CFU\;g^{-1}$ and $2log\;CFU\;g^{-1}$. In the organic fertilizers, coliforms and E. coli were detected in samples obtained from 4 and 1 companies, respectively, in the range of 1 to $3log\;CFU\;g^{-1}$ and $2log\;CFU\;g^{-1}$. In 3 out 32 compost samples, B. cereus was detected, while other pathogens were not detected. In 28 organic fertilizers, no pathogens were detected. The complete composting process can result in the elimination of pathogens in livestock manure compost and organic fertilizer. The results of this study could help to formulate microbiological guidelines for the use of compost in environmental-friendly agriculture. This research provides information regarding microbiological quality of livestock manure compost and organic fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.898-903
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• 2010

This study was carried out to estimate carbon emission using LCA (Life Cycle Assessment) and to establish LCI (Life Cycle Inventory) database of soybean production system. Based on collecting the data for operating LCI, it was shown that input of organic fertilizer was value of 3.10E+00 kg $kg^{-1}$ soybean and it of mineral fertilizer was 4.57E-01 kg $kg^{-1}$ soybean for soybean cultivation. It was the highest value among input for soybean production. And direct field emission was 1.48E-01 kg $kg^{-1}$ soybean during soybean cropping. The result of LCI analysis focussed on greenhouse gas (GHG) was showed that carbon footprint was 3.36E+00 kg $CO_2$-eq $kg^{-1}$ soybean. Especially $CO_2$ for 71% of the GHG emission. Also of the GHG emission $CH_4$, and $N_2O$ were estimated to be 18% and 11%, respectively. It might be due to emit from mainly fertilizer production (92%) and soybean cultivation (7%) for soybean production system. $N_2O$ was emitted from soybean cropping for 67% of the GHG emission. In $CO_2$-eq. value, $CO_2$ and $N_2O$ were 2.36E+00 kg $CO_2$-eq. $kg^{-1}$ soybean and 3.50E-01 kg $CO_2$-eq. $kg^{-1}$ soybean, respectively. With LCIA (Life Cycle Impact Assessment) for soybean production system, it was observed that the process of fertilizer production might be contributed to approximately 90% of GWP (global warming potential). Characterization value of GWP was 3.36E+00 kg $CO_2$-eq $kg^{-1}$.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.85-94
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• 2007

To determine the influence of food waste compost (FWC) application on paddy soil, FWC was applied to the paddy soil and then compared with farmer's practice as to the effects on rice and soil environment. Initially, pig manure compost (PMC) had high content of phosphorus ($15g\;kg^{-1}$) and potassium ($23g\;kg^{-1}$), while FWC had high content of total nitrogen ($13g\;kg^{-1}$) and salinity ($18.5g\;kg^{-1}$). Comparison was also made between chemical fertilizer and FWC use as a trial in the paddy field under the clay loam and sandy loam soil. In the panicle formation stage, chemical fertilizer application was proper in clay loam while PMC application was proper in sandy loam. However, chemical fertilizer produced higher yield compared to compost treatment, both on clay loam and sandy loam with 20~25% and 17~19%, respectively. The lower yield in sandy loam maybe due to slow mineralization of compost such that the crop did not effectively use it. Organic matter content in paddy soil after experiment was higher in FWC and PMC plots compared to that in chemical fertilizer plots. But the other soil properties were comparable. Therefore, the FWC compost had little effect on soil when it use as a trial in paddy field. Likewise, after the application of FWC as a trial, analysis of nitrate nitrogen and ammonium nitrogen in the surface water and 60 cm depth of paddy soil water nine days after planting was done. Results revealed that concentration of ammonium nitrogen was similar to irrigation water while nitrate nitrogen concentration was not detected, and hence did not contribute to water pollution. It is concluded that the application of FWC in the paddy field had not affected on environmental pollution in the paddy field. But its use as compost during rice culture reduced yield quantity. Such study should include selection of compost material, amount and method of compost application.

• Economic and Environmental Geology
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• v.54 no.5
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• pp.535-547
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• 2021

Aggregate is an essential construction material, and the demand is increasing every year. Aggregate has different properties in each region, and it is difficult to supply it over long distances due to its quantity and weight. For the stabilization of aggregate supply and demand, regional aggregate resource surveys have been conducted since 1993 in Korea. In this study, an aggregate resource survey was conducted in Goyang City to understand the characteristics of aggregate distribution as part of the annual regional aggregate resource survey in 2020. Goyang City has a high mountainous area to the east, and the southwestern part shows a topography where a wide flatland develops. It has 18 small streams originated from the eastern mountainuos area and 1 large stream Han River. The drilling data shows that thickness of the Quaternary deposits tend to deepen toward the south. The aggregate reserves are relatively abundant, the depth of the aggregates are relatively deep. Changes in the depth of the Quaternary deposits and the amount of aggregate in Goyang are seems to be closely related to the activities of the Han River rather than the sedimentation characteristics from the upstream to the downstream of the small streams. This characteristics show a similar tendency to the distribution of aggregates in adjacent regions to the west coast in Korea. Therefore, the regions that close to west coast have a high probability of aggregate reserves around relatively large-scale streams flowing into the west coast.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.419-428
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• 2021

In order to develope a mobile-based greenhouse energy calculation program, firstly, the overall thermal transmittance of 10 types of major covers and 16 types of insulation materials were measured. In addition, to estimate the overall thermal transmittance when the cover and insulation materials were installed in double or triple layers, 24 combinations of double installations and 59 combinations of triple installations were measured using the hotbox. Also, the overall thermal transmittance value for a single material and the thermal resistance value were used to calculate the overall thermal transmittance value at the time of multi-layer installation of covering and insulating materials, and the linear regression equation was derived to correct the error with the measured values. As a result of developing the model for estimating thermal transmittance when installing multiple layers of coverings and insulating materials based on the value of overall thermal transmittance of a single-material, the model evaluation index was 0.90 (good when it is 0.5 or more), indicating that the estimated value was very close to the actual value. In addition, as a result of the on-site test, it was evaluated that the estimated heat saving rate was smaller than the actual value with a relative error of 2%. Based on these results, a mobile-based greenhouse energy calculation program was developed that was implemented as an HTML5 standard web-based mobile web application and was designed to work with various mobile device and PC browsers with N-Screen support. It had functions to provides the overall thermal transmittance(heating load coefficient) for each combination of greenhouse coverings and thermal insulation materials and to evaluate the energy consumption during a specific period of the target greenhouse. It was estimated that an energy-saving greenhouse design would be possible with the optimal selection of coverings and insulation materials according to the region and shape of the greenhouse.

• Korean Journal of Labor Studies
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• v.24 no.1
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• pp.107-156
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• 2018

This article examines the history of the in - house subcontracting and the stabilization of labor - management relations in the steel industry in Japan. The ratio of in-house subcontract workers among steel workers has increased steadily until the mid-2000s, and about 70% in case of the largest company. In-house subcontracting was used as a strategy of the company to increase the quantity flexibility of employment and to save labor costs. The in-house subcontracting company needed company-specialized skills, and the internal labor market was formed because the rate of full-time workers was high and the turnover rate was low. The in-house subcontractor introduced long-term business relationship with the steel factory by introducing the equipment and materials necessary for the performance of the work, and the factory implemented the productivity improvement policy of the in-house subcontractor, and the win-win relationship between the factory and in-house subcontractor was developed. The trade union did not oppose the idea that the expansion of in-house subcontracting contributed to corporate profits, the stability of employment of the members and maintenance of their working conditions. Since 2000, the steel factory has pursued the transformation of in - house subcontractors into subsidiaries, which has been supported by capital relations. By the way, since the mid-2000s, there has been an increase in the number of regular workers' employment. The major factors are as follows: more strengthened compliance with laws and regulations, the higher quality request of customers, stricter keeping of deadlines, and problem in recruiting of workers at in-house subcontract companies. The wage gap between the factory and in - house subcontracting was less at company B than at company S, and the wage level of in - house subcontracting was about 90% of the factory at company B. The relatively small gap at company B seems to be due to the union's movement of narrowing the gap, low market dominance and unfavorable labor market. The internal labor market has been formed in the in-house subcontracting, and the wage gap is not large, and the possibility of labor disputes is low. Industrial relations are stable in the in-house subcontract company as well as the factory. The stabilization of labor-management relations in the steel industry in Korea is required to reduce the wage gap between the factory and in-house subcontract enterprises by raising productivity and expanding the internal labor market at in-house subcontract enterprises.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.19-30
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• 2019

Objective of this study was to develop an organic fertilizer utilizing domestic livestock horn meal and to investigate the application effect of rice and eggplant. The possibility of utilization of livestock horn meal as an organic resource to replace imported expeller cake fertilizer was examined. In order to select domestic organic resources with high nitrogen content, 8 kinds of organic matter such as chicken manure, fish meal, soybean meal, sesame meal, perilla meal, blood meal, livestock horn meal, and beer sludge were analyzed and organic resources with high nitrogen content were selected. In addition, the conditions for the production of organic fertilizers that can be used in organic agriculture were established by mixing of the rice husk biochar and the rice bran as the supplements with the raw materials for mixing ratios. The content of total nitrogen (T-N) in the livestock horn meal was 12.0 %, which was the next low in 13.5 % blood meal. The content of total nitrogen was 5.9 ~ 7.9 % in fish meal and oil cakes. Total nitrogen content of non-antibiotic chicken manure for organic farming was 3 % and nitrogen content in beer sludge was 3.5 %. Organic fertilizer was produced by using biochar, rice bran as a main ingredient of non-antibiotic chicken manure, livestock horn meal and beer sludge. Compared to nitrogen content (4.0 to 4.2 %) of imported expeller cake fertilizer (ECF), the nitrogen content of organic fertilizer utilizing domestic livestock horn meal is as high as 7.5 %. The developed organic fertilizer is met as Zn 400 mg/kg, Cu 120 mg/kg the quality of organic agricultural materials such as or less. To investigate the effect of fertilizer application on the crops, prototypes of developed organic fertilizer were used for the experiment under selected conditions. As a result of application the developed organic livestock horn meal fertilizer (LHMF) for cultivation of the rice and eggplant, the application quantity of the developed organic LHMF 100 % was decreased by 40 % compared to that of the mixed expeller cake fertilizer (MECF). The application of LHMF, which refers to the application rate corresponding to the nitrogen fertilization recommended by the soil test, was reduced by 40% compared to the application rate of MECF, but the same results were obtained in crop growth and yield. The selection of a new high concentration nitrogen source utilizing domestic organic resources and the development of organic fertilizer is the starting point of the research for substitution of imported ECF using domestic local resources at the present time that the spread of eco-friendly agriculture is becoming increasingly important. If it is expanded in the future, it is expected to contribute to the stable production of eco-friendly agricultural products.

• Korean Journal of Organic Agriculture
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• v.27 no.1
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• pp.87-100
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• 2019

The study was initiated to compare crop productivity as affected by a long-term application with homemade liquid fertilizers in leading organic cucumber (Cucumis sativus L.) farms in Suncheon and Kimcheon provinces. A Suncheon farm have applied an EM (effective organism) liquid fertilizer for one year and fifteen years, designating as EM 1-year and EM 15-year plots, respectively, with 4-year and 5-year application of native microbes-liquid fertilizer in Kimcheon farm, designating as Micro 4-year and Micro 5-year plots, respectively. pH in the EM-liquid fertilizer was high to approximately 7.7, and EC in the Micro-liquid fertilizer was 0.1 dS/m higher than those of EM-liquid fertilizer, with similar macro-nutrient concentrations observed in the both liquid fertilizers. Soil EC was the highest to the 10.0 dS/m for the liquid fertilizer with EM 1-year and showed less than 1.5 dS/m for other liquid fertilizer plots. Micro-liquid fertilizer plots had soil OM contents less than 20 g/kg, which was approximately two times less than those of EM plots. Soil microbial properties were not significantly different among the liquid fertilizer plots. SPAD and PS II values were significantly increased by EM 15-year plots with high levels of soil OM and EC. Liquid fertilizer plot with EM 1-year had high concentrations of T-N, Ca, and Na in the cucumber crops but low concentrations of P and Mg, in particular for low K of 1.2% which was two times less than those of desired level for an optimum cucumber growth. The lowest fruit yield was observed for the liquid fertilizer plot with EM 1-year with the highest soil EC accumulated. Liquid fertilizer plot with EM 15-year produced the expanded volume of crop canopy and increased fruit yield. Therefore, long-term of continuous application with an organic liquid fertilizer would have sustainably improved soil stability and the crop productivity.

• Clean Technology
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• v.27 no.1
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• pp.1-8
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• 2021

Due to the negative impacts of microplastics (MPs) on the ecosystem, the investigation of its occurrence and its treatment from sewage and wastewater treatment plants (WWTPs) have received a lot of attention in the recent years. Most MPs are precipitated and removed with the sludge during the treatment process. Proper sludge management is immensely necessary to avoid MP exposure in the environment. However, the domestic research on this aspect is limited. This study reviews appropriate sludge management approaches to decrease environmental MP exposure. This can be achieved through investigating sludge generation and treatment, regulation laws and government policy trends with an emphasis on WWTPs. The ratio of sludge in sewage treatment plants has been observed to be highest in recycling followed by incineration and landfills. Recycling is the highest in fuel followed by construction materials and composting. For WWTPs, the highest ratio is in recycling followed by fuel and landfills, and recycling is confirmed in the following order: incineration > after composting > after solidification > earthworm breeding. Treatment approaches that can increase the exposure of MPs to the ecosystem are considered to be used in landfills and agricultural fields. However, this method is not appropriate given the insufficient capacity of domestic landfills and the sufficient supply of existing chemical and animal manure fertilizers. Instead, it would be rational in terms of environmental preservation to expand the use of fuel and energy in connection with the new and renewable energy policy, and to actively seek the use of sub-materials for construction materials. In order to secure the basic data for the effectiveness of future planning and revision of related laws, it is required to perform an in-depth investigation of the sludge supply and demand status along with the environmental and economic effects.

• Journal of the Daesoon Academy of Sciences
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• v.35
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• pp.359-392
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• 2020

In this paper, we examined the development of Chinese Taoist architecture, its cultural implications, and comprehensively summarized the core principles of the Taoist ecological ideas that are reflected in Taoist architecture. This is a groundwork for exploring an ideological model for sustainable ecological architecture in modern cities. Taoist architecture has a long history that has led to changes, developments, and a gradual maturation. Zhi (治), Lu (廬), and Jing (靖), were the first architectural forms of the early Taoist body. These formed the basis for the future development of Taoist Courts (宮觀). The state-sponsored government-run Taoist Courts established from the time of the North and South Dynasties to the time of Tang Dynasty led to a constant standardization of the rites, and these Courts gradually became more and more formalized. Since the establishment of Quanzhenjiao (全眞敎) in the early 12th century, a movement that emphasized putiy training, architecture for the ascetic practice emerged in remote natural spaces suitable for strict ascetic practices. Meanwhile, in Taoist architecture, the type and structure of buildings were strengthened in order to worship various gods. The various Taoist Courts established through this historical process embody the elements, institutions, and ecological ideas of Taoist culture. Taoist architecture basically pursued the idealism of Paradise in a Deep Cave (洞天福地) and adopted a feng-shui theory of using natural terrain artfully in selecting a place and building a layout. This was reflected through their ecology. Meanwhile, Taoist architecture does not destroy the balance of nature by emphasizing the utilization of local natural resources whenever possible while selecting building materials according to the principles of yinyang and the five movements (陰陽五行). In addition, Taoism aims to select simple places for practising asceticism and ancestral rituals whenever possible because of the need to maintain a simple mind, suppress desire, and return to a state of purity. This attitude is an indication of a kind of simple ecological ideas and value of frugality easily found in Taoism. The ecological ideas of Taoism provide abundant resources for considering solutions to the ecological crisis that arises in the creation of residential environments. Through the ecological ideas of Taoism, we can find a direction to understand the relationship between human beings and nature while creating new, sustainable residential environments.