• Environmental Engineering Research
• /
• 제23권1호
• /
• pp.70-75
• /
• 2018

A pilot scale anaerobic fixed-bed with a reactor volume of $2.8m^3$ was built to treat slaughterhouse wastewater. Bamboo rings were chosen as support media mainly because of their cheaper price in underdeveloped countries. Even with their lower porosity and specific surface, the reactor performance showed a maximum 95% COD removal efficiency at an organic loading rate (OLR) of $1kg\;COD/m^3-d$ with its corresponding hydraulic retention time (HRT) of 7.5 d. At a higher OLR of $4.0kg\;COD/m^3-d$, the COD removal efficiency of 75% was achieved with an HRT of 2 d. No big difference in COD removal efficiencies was found between the reactors operated in both upflow and downflow modes. Their operational behavior and effluent characteristics were similar. The effluent COD/TKN ratio of 6.67 at an OLR of $4.0kg\;COD/m^3-d$ was only marginal acceptable range for a subsequent biological denitrification process. Otherwise carbon supplementation is required at a lower OLR.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2006년도 학술발표회 논문집
• /
• pp.535-539
• /
• 2006

GIS-based integrated management system was developed for the treated wastewater to be reused as agricultural water. The major scopes of this research includes developing different types of system such as connecting data of wastewater treatment plants to data of hydraulic structures and paddy field ; separating spatial data into the watershed boundary and the agricultural water boundary ; and estimating applicable site for reuse. This system can enable to provide more scientific support to manage information of effluent and agricultural data utilizing GIS techniques.

• 지구물리
• /
• 제7권1호
• /
• pp.51-60
• /
• 2004

시간이 경과함에 따라 상수도 관망시설은 부식 혹은 파손 등의 이유에 의하여 통수능의 저하 및 통수 불가능의 위험에 처할 수 있다 이에 따라 계속적인 관리의 적용을 위해서는 각 관망의 교체 시기 및 개선 방안에 대한 연구가 필요하며 이의 효율적인 방안으로서 최적화 기법 혹은 의사결정 지원 시스템 등의 구성이 요청된다 그러나 현재의 연구 동향들로서는 수리특성의 변화만을 관망 교체의 주 고려 대상으로 인식하고 공업 경영학적 계획을 고려하고 있지 못하다 본 연구에서는 이들 두 가지 개념으로서의 관망 개량 프로그램을 제시하였으며 대전광역시에 대하여 기초적으로 적용하여 보았다

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2002년도 추계학술발표회요약집
• /
• pp.155.2-155
• /
• 2002

A visual environment for system analysis codes (hereinafter called "ViSA") has been developed to support code users in their input preparations, code executions, and output interpretations. ViSA provides a more convenient way for base input data generation and modification on a user-friendly basis. It also provides on-line graphical displays to give an in-depth understanding of transient thermal-hydraulic behaviors in nuclear power plants. This paper presents the main features of ViSA.

• Membrane and Water Treatment
• /
• 제4권2호
• /
• pp.83-93
• /
• 2013

In the present investigation, were synthesized composite membranes prepared by simultaneous casting of two polymer solutions using the technique of phase inversion by immersion / precipitation. The support layer was prepared using polyethersulfone and polysulfone as base polymer and for the top layer was used sulfonated polysulfone (SPSU) with 50% sulfonation degree. The morphology of the resulting membranes were characterized by scanning electron microscopy (SEM). The final results showed that it is possible to prepare composite membranes by simultaneous casting of two polymer solutions with adherence between the two layers. Regarding the permeation tests, the developed membranes presented values of hydraulic permeability within the range of commercial nanofiltration (NF) membranes. Values rejection of 80% ammonium ions can be increased by using a SPSU with a greater degree of sulfonation.

• 한국화재소방학회논문지
• /
• 제17권4호
• /
• pp.92-97
• /
• 2003

침수 경험이 있는 지역에 있어서 수해에 따른 인명 피해의 발생을 방지하기 위해서는 지역주민의 피난행동양식의 분석과 수방관련정보의 공개 등과 같은 적극적인 재해 대응대책이 중요하다. 피난행동을 규정하는 심리적인 영향요인에 대해서는 주민의 의식조사를 토대로 내$.$외적인 요인으로 분류하여 분석하였다. 또한 수리모형 실험을 통하여 적정 피난수심을 유도하였으며 이와 같은 노력은 금후 침수심을 고려한 피난훈련을 통하여 주민의 수해에 대한 경각심을 고취시킴으로써 효과적인 수방활동에 기여할 것이다.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
• /
• 한국우주과학회 2004년도 한국우주과학회보 제13권2호
• /
• pp.262-265
• /
• 2004

As a cryogen, LOx is a light blue, odorless, transparent liquid. Also it is not shock sensitive and does not decompose. However, it is a strong oxidizer and will vigorously support combustion. Therefore all harmful contaminants (such as grease, oil, fingerprint and organic materials) that could cause malfunctions, fires, or explosions in a oxygen environments must be completely removed prior to the introduction of oxygen. Especially, grease ingredient located inside of the LOx supply line, pipe and PHS (Pneumo-Hydraulic System) part can make drastic chemical reaction with oxygen. Therefore, to protect rapid reaction such as explosion, grease ingredient must be surely eliminated by a regular and irregular degreasing. Study on the availability, effectiveness and selection of degreasing detergents and method is described in this paper, and it will be useful for the construction and management of IPP test facility.

• Environmental Engineering Research
• /
• 제19권2호
• /
• pp.117-122
• /
• 2014

Indexes of safety, restoration, damage impact, and management reliability were developed to assess reliability of drinking water distribution networks (DWDNs) management. The developed indexes were applied to evaluate the reliability of the pipeline management stage during unexpected mechanical and hydraulic accidents of components. The results were used to support the decision-making process in effective management and maintenance by enhancing the administrator's system understanding and by helping to create appropriate maintenance and management policies. The results of this study indicated that application of a management reliability index to assess DWDNs reliability may help create a more effective plan for establishing DWDNs management and maintenance.

• 공학논문집
• /
• 제4권1호
• /
• pp.137-149
• /
• 2002

시간이 경과함에 따라 상수도 관망시설은 부식 혹은 파손 등의 이유에 의하여 통수능의 저하 및 통수 불가능의 위험에 처할 수 있다. 이에 따라 계속적인 관리의 적용을 위해서는 각 관망의 교체 시기 및 개선 방안에 대한 연구가 필요하며, 이의 효율적인 방안으로서 최적화 기법 혹은 의사결정 지원 시스템 등의 구성이 요청된다. 그러나, 현재의 연구 동향들로서는 수리특성의 변화만을 관망 교체의 주 고려 대상으로 인식하고, 공업 경영학적 계획을 고려하고 있지 못하다. 본 연구에서는 이들 두 가지 개념으로서의 관망 개량 프로그램을 제시하였으며, 대전광역시에 대하여 기초적으로 적용하여 보았다.

• Nuclear Engineering and Technology
• /
• 제54권9호
• /
• pp.3551-3566
• /
• 2022

The STELLA program was launched to support the PGSFR development in 2012 and for the 2nd stage, the STELLA-2 facility was designed to investigate the integral effect of safety systems including the comprehensive interaction among PHTS, IHTS and DHRS. In STELLA-2, the long-term transient behavior after accidents can be observed and the overall safety aspect can also be evaluated. In this paper, the basic design concept from engineering basis to specific design is described. The design was aimed to meet similarity criteria and requirements based on various non-dimensional numbers and the result satisfied the key features to explain the reasoning of safety evaluation. The result of this study was used to construct the facility and the experiment is on-going. In general, the final design meets the similarity criteria of the multidimensional physics inside the reactor pool. And also, for the conservation of natural circulation phenomena, the design meets the similarity requirements of geometry and thermo-dynamic behavior.