• Asian-Australasian Journal of Animal Sciences
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• 제30권10호
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• pp.1500-1506
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• 2017

Objective: High $NH_3$ emissions from poultry houses are reported to have negative impacts on health, welfare and safety of birds and humans, and on the environment. Objective of the present study was to determine the effects of two litter amendments on the $NH_3$ levels in broiler closed houses under hot-humid conditions. Methods: Giving a completely randomize design, nine closed houses, each housed 32,500 birds on paddy husk litter, were randomly allocated into two treatment (Mizuho; a bacterial culture mix and Rydall OE; an enzymatic biocatalyst) and control groups. $NH_3$ levels were determined thrice a day (0600, 1200, and 1800 h), at three heights from the litter surface (30, 90, and 150 cm), at 20 predetermined locations of a house, from day 1 to 41. Results: Rydall significantly reduced the $NH_3$ level compared to control and Mizuho. $NH_3$ levels at 30 cm were significantly higher than that of 90 and 150 cm. The $NH_3$ levels at 30 cm height were higher than 25 ppm level from day 9, 11, and 13 in Mizuho, control, and Rydall groups, respectively to day 41. $NH_3$ levels at 150 cm height were higher than maximum threshold limit of 50 ppm for human exposure from day 12, 14, and 15 in Mizuho, control, and Rydall groups, respectively to day 33. Being significantly different among each other, the $NH_3$ level was highest and lowest at 0600 and 1800 h. Litter amendments had no significant effects on growth performance. Rydall significantly increased the litter N content on day 24. Conclusion: It was concluded that the $NH_3$ levels of closed house broiler production facilities under tropical condition are so high that both birds and workers are exposed to above recommended levels during many days of the growing period. Compared to microbial culture, the enzymatic biocatalyst was found to be more effective in reducing $NH_3$ level.

• 한국토양비료학회지
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• 제46권4호
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• pp.281-287
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• 2013

Due to its high salt content and poor physical properties in reclaimed tidal lands, it is important to ameliorate soil physical properties to improve the efficiency of desalination. The objective of this study was to evaluate the changes of soil properties at Saemangeum reclaimed tidal saline soil with various soil amendments. Field experiment was conducted at Saemangeum reclaimed tidal land in Korea and the dominant soil series was Munpo series (coarse loamy, mixed, nonacid, Mesic, Typic, Fluvaquents). Woodchips, crushed-stone, oyster shell, coal bottom ash, and rice hull were added as soil amendments and mixed into surface soil to improve soil physical properties. There was large variability in soil hardness, but oyster shell treatment was significantly lower soil hardness at surface layer. Soil hardness was not significantly different below 15 cm depth. Infiltration rate was also significantly greater at oyster shell treatment. This may be due to the leaching of Ca ions from oyster shell and improved soil properties. However, there was no statistical significant difference of the soil bulk density, moisture content, and porosity. Improved physical properties increased desalinization rate in soil and retarded the resalinization rate when evapotranspiration rate was high. Although soil salinity was significantly decreased with oyster shell amendment, soil pH was increased that should be made up as a soil amendment. Our results indicated that oyster shell application increased infiltration rate and improved soil hardness, and thus oyster shell could be used to improve soil salinity level at Saemangeum reclaimed tidal saline soil.

• 한국토양비료학회지
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• 제50권5호
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• pp.401-408
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• 2017

Organic amendments such as animal waste compost, lime-bordeaux mixture, and lime sulphur mixture contain heavy metal(loid)s which are toxic to human being, animal, and plant. The objective of this study was to compare heavy metal(loid)s contamination of soil between conventional and organic farm. Soil samples were collected from 10 conventional and 38 organic fruit farms. At each sampling point, top (0~15 cm) and sub soil (15~30 cm) were taken using hand auger. Total concentration for arsenic (As), cadmium (Cd), copper (Cu), nikel (Ni), lead (Pb), and zinc (Zn) in the collected soil were measured. The pollution index (PI) for heavy metal in organic farms indicated it was unpolluted area. However, mean value of PI for organic farms (0.143) was higher than that for conventional farms (0.122). High Geoaccumulation index (Igeo) for Cu, Pb, and Zn implied that grape farms were more polluted than others fruit farms because a lot of lime-bordeaux mixture and lime sulphur were applied in organic grape farms. Especially, top soils showed higher level of contamination than sub soil. Based on the above results, organic amendments might cause accumulation of heavy metals in soil. Therefore, particular attention should be paid for concentration of Cu, Pb, and Zn, when organic amendments are used in the organic fruit farms.

• 경영과정보연구
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• 제33권4호
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• pp.63-75
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• 2014

본 연구는 시장구조에 초점을 맞추어 산업의 표준화 활동 결정요인을 우리나라 제조업에 대해서 계량적으로 검증한다. 단체표준 제정 및 개정 여부를 산업 차원에서 표준화 활동의 대리변수로 삼았고, 그 결정요인으로 시장구조 이외에도 기술적 기회, 자본집약도, 수출비율, 산업특성(조립산업 여부) 등을 고려하였다. 분석대상은 식료, 섬유, 화학, 비금속광물, 금속, 전기전자, 기계, 자동차, 조선 등 9개 업종이며, 2006-2009년 기간 동안 혼용자료(pooling data)를 사용하였다. 추정방법으로는 로지스틱 회귀분석(logistic regression analysis)을 활용하였다. 연구결과, 시장집중도는 산업의 단체표준화 활동에 아무런 영향을 미치지 않는 것으로 분석되었다. 이는 독점적 시장일수록 소수의 대기업들이 공적 표준(de jure standards)인 단체표준보다는 '사실상의 표준(de facto standards)'에 더 관심을 가지고 있을 가능성을 보여준다. 시장구조 이외의 변수의 경우에는 기술적 기회와 조립산업 여부는 단체표준화 활동에 대해서 정(+)의 유의한 효과를 보인 반면, 자본집약도와 수출비율은 단체표준화와는 연관이 없는 것으로 분석되었다.

• 한국토양비료학회지
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• 제50권6호
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• pp.663-673
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• 2017

Heavy metal(loid) contamination of rice is the main issue in abandoned metal mine area with regard to food safety. A field study was conducted in mine area to see if soil amendments treatment including calcium superphosphate, sulfur, steel slag and S-containing fertilizer could reduce As and/or Cd content in rice grain and increase the growth of rice. The As content in brown rice reduced to 60% compared to the control only in $7.0Mg\;ha^{-1}$ of steel slag treatment. Cd reduction in rice was thought to be not the effect of amendments but the result from the difference in growth and development of rice plant and this could be ascribed to low soil Cd availability to rice plant. Compared with control, increased rice yield of cultivar Hwanggeumnuri was 1.3~2.2 and $1.5Mg\;ha^{-1}$ in calcium super phosphate and S-containing fertilizer treatment, respectively and the trend was also observed in cultivar Ungwang. However, steel slag treatment reduced the Ungwang yield by $0.4{\sim}0.9Mg\;ha^{-1}$. Future work will be needed to establish the agricultural measure with which secure the safety and yield of rice simultaneously.

• 한국환경농학회지
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• 제38권1호
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• pp.17-22
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• 2019

BACKGROUND: Soil contamination of As is a very sensitive environmental issue due to its adverse impact on human health and different characteristics with other heavy metals. With public awareness of As poisoning, there has been growing interest in developing guideline and remediation technologies for As-contaminated soil. The objective of this research was to evaluate the effectiveness of stabilizing amendments and soil dressing methods on the mobility of As in the contaminated rice paddy soils nearby mining area. METHODS AND RESULTS: Different amendments were mixed with surface and subsurface contaminated soils at a ratio of 3% (w/w) and monitored for five months. Three different extractants including 0.01M $CaCl_2$, TCLP, and PBET were used to examine As bioavailability in the soil and the concentration of As in rice grain was also measured with an inductively coupled plasma (ICP) spectroscopy. The results showed that all amendment treatments decreased As concentration compared to the control. Especially, coal mine drainage sludge (CMDS) treatment showed the highest efficiency of decreasing As concentration in the soil and rice grain. The values of Pearson correlation (r) between As concentrations in the soil and rice grain were 0.782, 0.753, and 0.678 for $CaCl_2$, TCLP, and PBET methods, respectively. Especially, $CaCl_2$ method was highly correlated between As concentrations of the soil and soil solution (r=0.719), followed by TCLP (r=0.706), PBET (r=0.561) methods. CONCLUSION: Stabilizing amendments can effectively reduce available As concentration in the soils as well as soil solution, and thereby potentially mitigating risks of crop contamination by As.

• 농업과학연구
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• 제50권4호
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• pp.967-976
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• 2023

Biochar is emerging as a promising substance for achieving carbon neutrality and climate change mitigation. It can absorb several nutrients via ion bonding on its surface functional groups, resulting in slow dissociation of the bonds. Biochar, like organic fertilizers, contributes to sustainable nutrient management. The purpose of this study was to investigate the effects of nutrient-coated biochar amendments on leafy vegetables production and soil fertility. The nutrient-coated biochar was produced by soaking rice husk biochar in a nutrient solution containing nitrogen (N), phosphorus, and potassium for 24 hours. Nutrient-coated biochar and organic fertilizers were applied to soil at a rate of 120 kg·N·ha^-1. The growth components of the leafy vegetables showed that nutrient-coated biochar led to the highest fresh weight (FW) of both lettuce and kale (i.e., 146.67 and 93.54 g·plant^-1 FW, respectively). As a result, nutrient-coated biochar amendments led to superior yield compared to the control treatment and organic fertilization. The elemental composition of leafy vegetables revealed that soil amended with nutrient-coated biochar resulted in higher nutrient contents, which was attributed to the high nutrient contents supplied by the rice husk biochar. Soil amendment with nutrient-coated biochar positively enhanced the soil fertility compared to amendment with organic fertilizer. Therefore, nutrient-coated biochar is a promising substance for enhancing agronomic performance of leafy vegetables and improving soil fertility.

• 대한예방한의학회지
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• 제28권1호
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• pp.31-42
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• 2024

Objective : In order to understand the changes in domestic approval regulations applicable to traditional Korean medical device companies, this article will explain the major amendments 「Regulation on Medical Device Approval Report Review, etc.」 from 2005 to the present on a year-by-year basis, and provide a counter plan to the recent changes in approval regulations. Methods : We analysed the changes in approval regulatory amendments related to the traditional Korean medical devices from 2005 to the present. Results : The Ministry of Food and Drug Safety is continuously improving medical device approval regulations to ensure the global competitiveness of domestic medical devices and contribute to the improvement of public health. Recent major approval regulatory amendments include the establishment of a review system for software medical devices and digital therapeutics, the recognition of real world evidence materials, the introduction of a biological evaluation of medical devices within a risk management process and a medical device approval licence renewal system. Conclusions : It is expected that the range of medical devices available to Korean medicine doctors will continue to expand in the future through the provision of non-face-to-face medical services and the development of advanced and new medical devices, as well as wearable medical devices and digital therapeutics. In order to increase the market entry potential of traditional Korean medical devices that incorporate advanced technologies such as digital technology and AI-based diagnosis and prediction technology, it is urgent that the government provide significant support to traditional Korean medical device companies to improve approval regulatory compliance.

• 한국조경학회지
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• 제39권5호
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• pp.119-126
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• 2011

조경공사 표준품셈은 표준적이고 보편적인 공종과 공법들로 구성되어 있다. 그러나 최근 조경분야는 건설기술의 발전과 공사품질의 고급화가 요구되고 있는 실정이다. 그러나 현행 조경공사 표준품셈으로는 이러한 변화에 대응하기에는 한계가 있다. 이에 본 연구는 조경공사 표준품셈의 발전방안을 제시하는 것이 중요하다고 판단하여 우선 개정들이 필요한 품셈 공종을 파악하였다. 개정이 필요한 공종을 파악하기 위하여 문헌고찰과 예비설문조사를 통하여 설문 항목을 선정하였으며, 선정된 항목들은 조경 분야 전문가 60명으로부터 응답을 받아 통계처리 하였다. 연구의 결과는 다음과 같다. 첫째, 조경공사 표준품셈에 대한 활용도는 식재공종의 품셈이 가장 높았다. 둘째, 신규로 추가될 필요가 있는 공종으로는 정지공사, 조경 구조물공사, 포장공사, 수경시설공사, 옥외 시설물공사들로 파악되었다. 셋째, 조경공사 품셈공종 분야에서는 설문응답자들의 66.7%가 개정이 필요하다고 응답하였고, 개정이 필요한 품셈 공종으로는 식재 공종에서는 대형수목, 조형수목, 수목가식, 수목하자 등으로 파악되었다. 굴취공종에서는 대형수목, 조형수목 등으로 파악되었다. 유지관리공종에서는 전정폐기물 처리 품셈, 정원석 쌓기 및 놓기 공종에서는 돌틈 식재 품셈, 떼붙임 및 초류파종 공종에서는 현실적인 잔디규격의 품셈을 필요로 한다고 응답하였다. 연구의 결과들을 바탕으로 조경공사 표준품셈의 발전방안을 제시하면, 조경 식물의 규격과 조경공사 품질에 대한 공종별 세부 품셈과 조경공사 품질에 영향을 미치는 품셈분야의 개정이 필요하다.

• 자원환경지질
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• 제54권1호
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• pp.21-33
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• 2021

국내 오염시나리오별 안정화 효율과 경제성이 뛰어난 안정화제를 선택하여 적용할 수 있도록, 국내외에서 연구된 대표적인 안정화제를 대상으로 국내 중금속 오염 현장 부지 특성별 중금속 안정화 효율이 높은 안정화제 순위를 결정하였다. 총 5종류의 오염시나리오를 가정하여 각각 해당되는 국내 오염부지 토양을 확보하였다. 국내외 활용도와 안정화 효율 연구 결과, 오염특성별 부지 시나리오에 적용 가능성 등을 고려하여 기존에 연구되었던 안정화제 13가지를 선정하였다. 선정한 오염 토양과 안정화제의 오염 가능성과 현장 적용 가능성을 평가하기 위하여 XRD/XRF 분석, 독성용출시험과 인공강우용출시험 등을 실시하였다. 부지 오염시나리오를 대표하는 5종류 오염 토양에 대하여 선정된 13종의 안정화제에 의한 비소, 수은, 납, 6가 크롬, 아연, 니켈, 구리 등 총 8종의 중금속(반금속인 비소 포함) 용출 저감 효과를 규명하는 용출 배치실험을 수행하였다. 총 5개 오염 토양에 대하여 13개 안정화제 주입 비율 3%, 5%, 7% 적용 시, 각 중금속(비소 포함)에 대한 중금속 용출 저감 효율이 안정화제를 주입하지 않은 토양 대비 20% 이상을 나타내는 안정화제 중에서 저감 효율이 높은 순위부터 5개 안정화제(Top 5)를 선택하였다. 각 안정화제에 대하여 안정화제 주입비율, 중금속 종류, 부지별 조건에 따라 수행된 배치실험 결과에 대하여 Top 5에 해당하는 총 횟수를 합산하여, 다양한 국내 부지 오염시나리오에 적용할 수 있는 안정화제의 순위를 결정하였다. 5개 오염 토양에 대하여 8개 중금속 항목별 용출 저감 효율이 20% 이상인 경우, 가장 안정화 효율이 높은 순위는 광산배수처리 슬러지(mine drainage treatment sludge), 산화철, 생석회, 소석회-석회석, 황화철, 바이오차 순으로 나타났다. 위 안정화제들에 대하여 안정화제의 효율대비 단가를 산정한 결과, 광산배수처리 슬러지, 석회석, 제강슬래그(비소의 경우), 생석회, 소석회 순으로 경제성이 높게 나타나 현장 적용성이 뛰어난 것으로 밝혀졌다.