• 한국물환경학회지
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• 제22권3호
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• pp.417-424
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• 2006

• 한국물환경학회지
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• 제28권6호
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• pp.804-812
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• 2012

This study contemplated domestic and other country's effluent limitation standards and suggested a methodology to establish technology-base limitation value. Current effluent limitation regulates industrial point sources discriminated by discharge flow rate and by regional distinction in Korea. Discharged $BOD_5$ load from large-scale plants(flow rate above $2,000\;m^3/day)$ exceeds 50% of overall industrial wastewater, which present rationale for discrimination based on plant size. However, regional distinction and pollutant- specific regulation might be insufficient to meet practical effectiveness of wastewater management policy, due to the nearly same limitation. Water quality data and treatment methods were investigated in hospital industry. And their distribution of effluent $BOD_5$ concentrations was statistically analyzed to suggest limitation value. Effluent $BOD_5$ concentrations showed lognormal distribution and $95^{th}$ percentile was corresponded to 87.9 mg/L, which could be suggested as tentative effluent limitation in hospital industry. The $95^{th}$ percentile of log-transformed distribution showed similar value of 86.5 mg/L. This study demonstrated reasonable methodology for establishing effluent limitation reflecting wastewater characteristic and treatment technology in separately categorized industry.

• 방사선산업학회지
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• 제9권4호
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• pp.199-207
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• 2015

Typical radiation cross-linked hydrogels has the characteristic that high water content, but low emission efficiency of active ingredients. Therefore, the hydrogel was prepared by the addition to collagen, which is closely related to the formation of skin wrinkles in biocompatibility and highly water-soluble carboxymethyl cellulose sodium salt (CMC) in order to preparation of hydrogels has excellent emission efficiency of active ingredients. Hydrogels were prepared by dissolving CMC and collagen each of 0.5%, 10% concentration in deionized water. Then, prepared hydrogels are performed by gamma-radiation at 1, 3, 5 kGy irradiation dose. The results showed that the gel fraction of after irradiated 3 kGy hydrogel was higher than before irradiated gelation as long as the 55.3%. The swelling rate of irradiated 3 kGy hydrogel was lower than the non-irradiated sample. The compressive strength of 3 kGy irradiated hydrogel was the highest. The visco-elastic did not show any significant differences, even after irradiation. The CMC hydrogel in this study suggested a potential use as a material for the mask pack for improved emission efficiency of the active ingredient and anti-wrinkles.

• 한국식품영양과학회지
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• 제37권10호
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• pp.1231-1237
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• 2008

포공영의 총 페놀함량에서는 열수 추출물 7.80$\pm$0.97 mg/g, 에탄올 추출물 9.12$\pm$0.51 mg/g으로 나타났다. 플라보노이드함량은 열수 추출물 54.20$\pm$1.95 mg/g, 에탄올 추출물 79.43$\pm$4.44 mg/g으로 항산화 활성에 관련된 페놀 및 플라보노이드 화합물들이 에탄올 추출물에 많이 존재함을 확인할 수 있었다. 전자공여능에 있어서도 포공영 에탄올 추출물이 열수 추출물 $IC_{50}$값에 비해 3배 정도의 뛰어난 활성을 보였다. 아질산염 소거능은 모든 pH 조건하에서 에탄올 추출물이 열수 추출물보다 높은 아질산염 소거능을 나타내었으며, pH가 증가할수록 감소하였다. SOD 유사활성을 측정한 결과 열수 추출물에서는 18.34$\sim$37.26 $\mu$g/mL, 에탄올 추출물에서는 16.60$\sim$49.03 $\mu$g/mL의 범위로 분석되었으며, 농도에 따른 유의적 증가현상을 나타내었다. Tyrosinase 및 elastase 저해활성은 모든 추출물에서 대조구에 비해 다소 약한 활성을 나타내었다. 포공영 추출물은 뛰어난 항산화 활성을 나타나 기능성 식품 및 화장품 소재로 개발 가능성이 높을 것으로 사료된다.

• 한국식품위생안전성학회지
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• 제23권2호
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• pp.98-107
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• 2008

오존은 불소 다음으로 강력한 산화력을 가지고 있으며 넓은 범위의 살균 스펙트럼을 가진 성분이다. 식품산업을 포함한 다양한 분야에서 오존이 가진 장점을 이용하기 위한 연구가 진행되었고 지금도 효율적인 이용을 위한 많은 연구들이 이루어지고 있다. 오존은 미국, 호주 및 일본 등에서는 이미 식품첨가물로 허가되어 사용되고, 국내에서도 2007년 11월에 오존수를 식품첨가물로 허가하면서 국내 식품산업계에서 오존수 이용에 대한 관심이 증가되고 있다. 오존을 이용한 살균방법은 다른 방법들과 비교해보면 초기 설비비에 비해 유지관리비가 저렴하고, 사용 후 부산물이 거의 없다는 장점을 가지고 있으며, 최근의 식품안전 요구증대와 맞물려 그 수요가 증가될 전망이다. 국내에서 오존수는 과일, 채소, 식육 등 식품의 원재료 처리하는 살균용제로서 주로 사용되고 있으나 실태조사의 결과에 따르면 이용사례는 극히 제한적이었다. 그러나 오존수 생성 기계장치의 국내 시장이 급속도로 확대되면서, 단체급식을 중심으로 점차 사용이 증가되고 있는 추세이다. 오존수는 오존을 좀 더 편리하게 이용할 수 있도록 물에 용존 시킨 상태를 말한다. 따라서 오존수는 오존의 용존량과 용존된 오존의 지속시간 등에 대하여 철저히 관리되어야 하며, 안전한 사용을 위해서는 배오존 농도 관리도 필요하다. 상기 관리항목들은 대부분이 기계장치의 자체성능과 직결되는 것이기 때문에 오존수 제조장치의 성능기준을 새롭게 정립할 필요가 있다.

• 디지털산업정보학회논문지
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• 제10권2호
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• pp.37-45
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• 2014

This paper is a study of the water sensor using a coaxial cavity resonator. This water sensor uses the resonant frequency variation of the coaxial cavity resonator when there is a water drop of the used coaxial cavity resonator. And we made resonant frequencies by controlling the input voltage of the oscillator which will be mainly resonated in the coaxial cavity resonator. First, we made the coaxial cavity resonator by simulating the resonator structure with the proposed size and we expect the resonant frequency from the simulation and then we decide the VCO from the result. Second, we made the water drop detecting sensor circuit and measured the water sensor. We decided the size of the resonator as inner conductor 5mm, outer conductor 14mm, the height of resonator 9.5mm, and the height of the glass 6mm from the simulated result. The simulated resonant frequencies are 3.09GHz and we made the VCO frequency ranges from 2.56GHz to 3.2GHz. The measured resonant frequency is 2.97GHz and the return loss is under -8. 4 dB at the center frequency. When the water is dropped on the glass of the resonator, the voltage has changed from 690mV to 145mV. It shows the proposed water sensor can detect the water by the resonant frequency variation of the resonator.

• Membrane and Water Treatment
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• 제5권2호
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• pp.123-146
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• 2014

Safe water has becoming a competitive resource in many parts of the world due to increasing population, prolonged droughts, climate change etc. The development of economical and stable materials and methods for providing the fresh water in adequate amounts is the need of the water industry. Nanomaterials have unique characteristics e.g., large surface areas, size, shape, and dimensions etc. that make them particularly attractive for removing various contaminants from polluted waters. Nanotechnology based multifunctional and highly efficient membrane processes are providing affordable solutions in the new era that do not rely on large infrastructures or centralizes systems. The objective of the current study is to review the possible applications of the membrane based nanomaterials/composites for the removal of various contaminations from polluted waters. The article will briefly overview the availability and practice of different nanomaterials based membranes for removal of bacteria and viruses, organic compounds and inorganic solutes etc. present in surface water, ground water, seawater and/or industrial water. Finally, recommendations are made based on the current practices of nanofiltration membranes in water industry for a stand-alone membrane filtration system in removing various types of contaminants from polluted waters.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.441-444
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• 2006

A lot of water is using in the paper mill for dilution, washing, sealing, and other process operation. As the regulation of water environment has been more tightened than ever before, water management in the paper mill becomes the most important task. Topics on reducing fresh water and increasing recycling water have been studied. Further, an interest in zero-effluent system has been increased. The pH of waste water in paper mill is usually weak acidic or neutral. The waste water in the paper mill includes water insoluble organic materials that are not easy to be dissolved in the water, inorganic materials that never react with water and chemical additives that are used to recycled fiber. This study investigated on the effect of various materials used in paper mill on COD. This data could be used to control the environmental load in paper mill. COD caused by raw materials and NBDCOD (Non Bio Degradable COD) after the activated sludge process are investigated in this study. Results obtained in this study can be used in a simulation program designed to control environmental load in the paper mill.

• 한국해양공학회지
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• 제33권4호
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• pp.364-376
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• 2019

When underwater blasting is conducted, both shock waves and water waves have an effect on adjacent coastal areas. In this study, an empirical formula for estimating the details of water waves caused by underwater blasting was applied to a non-reflected wave generation system, and a 3D numerical wave tank (NWT) was improved to reproduce the generation and propagation of such water waves. The maximum elevations of the propagated water waves were comparatively analyzed to determine the validity and effectiveness of the NWT. Good agreement was demonstrated between the empirical and simulation results. The generation and propagation of water waves were also simulated under each underwater blasting scenario for the removal of the Todo islet at the Busan Newport International Terminal (PNIT). It was determined that the water waves generated by the underwater blasting scenario examined in this study did not have a significant impact on the PNIT. In addition, multiple-charge blasting caused higher wave heights than single-charge blasting. As the amount of firing charge increased, the wave height also increased. Finally, larger water waves were generated during the later blasting conducted at a deeper depth as compared with an earlier blasting conducted at a relatively shallow depth.

• 사물인터넷융복합논문지
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• 제9권1호
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• pp.41-47
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• 2023

오늘날, 세계 인구성장률의 증가로 국제사회는 심각하게 식량문제 해결을 논의하고 있다. 식량문제 해결을 위한 대안으로는 양식산업이 대두되고 있다. 최근 양식산업의 혁신성장을 위해 4차 산업기술을 융합한 스마트 양식장이 보급되고 있으며, 전주기적 디지털화가 추진되고 있다. 양식산업에서 중요한 수질센서는 전기화학방식의 휴대용 센서를 사용하고 있으며, 이를 이용하여 개별적, 간헐적으로 수질을 체크하고 있어서 양식장 수질을 실시간 분석하고 관리하기가 불가능하다. 최근 광학 기반의 모니터링이 가능한 수질센서들이 개발되어 현장에 적용되고 있다. 그러나 수질센서의 상태정보를 알 수 없기 때문에 모니터링 데이터의 신뢰성을 보장할 수 없는 상황이다. 따라서, 본 논문에서는 데이터의 신뢰성을 확보할 수 있도록, 수질센서가 수집하는 모니터링 데이터를 기반으로 고장, 기준일탈, 유지보수, 점검 등의 수질센서 자가진단 상태를 파악할 수 있는 알고리즘을 제안한다.