• Journal of Korean Society on Water Environment
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• v.27 no.3
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• pp.322-328
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• 2011

This study was performed to investigate the characteristics of nutrient removal of municipal wastewater in the membrane bioreactor system with the different types of membrane. Membrane bioreactor consists of three reactors such as two intermittent anaerobic and the submerged membrane aerobic reactor with flat sheet and hollow fiber membrane, respectively. The removal efficiencies of $COD_{cr}$, BOD, SS, TN and TP on the flat sheet membrane bioreactor were 94.3%, 99.0%, 99.9%, 70.3% and 63.1%, respectively. In addition, The removal efficiencies of $COD_{cr}$, BOD, SS, TN and TP on the hollow fiber membrane bioreactor were 94.0%, 99.3%, 99.9%, 69.9% and 66.9%, respectively. The estimated true biomass yield, specific denitrification rate (SDNR), specific nitrification rate (SNR) and phosphorus removal content on the flat sheet membrane bioreactor were $0.33kgVSS/kgBOD{\cdot}d$, $0.043mgNO_3-N/mgVSS{\cdot}d$, $0.031mgNH_4-N/mgVSS{\cdot}d$, and 0.144 kgP/d, respectively. In addition, the estimated true biomass yield, specific denitrification rate (SDNR), specific nitrification rate (SNR) and phosphorus removal content on the hollow fiber membrane bioreactor were $0.30kgVSS/kgBOD{\cdot}d$, $0.067mgNO_3-N/mgVSS{\cdot}d$, $0.028mgNH_4-N/mgVSS{\cdot}d$, and 0.121 kgP/d, respectively. There was little difference between the flat sheet and hollow fiber on the nutrient removal efficiencies except SNR and SDNR. These differences between them were caused by the air demand to prevent the membrane fouling. The flux and oxygen demand for air scouring were $19.0L/m^2/hr$ and $2.28m^3/min$ for the flat sheet membrane, and $20.7L/m^2/hr$ and $1.77m^3/min$ for the hollow fiber membrane on an average.

• 월간 기계설비
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• s.288
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• pp.62-74
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• 2014

가족끼리 놀러 가기로 했다. 한 아이는 수족관, 다른 아이는 동물원을 가자고 조른다. 부모는 어느 쪽으로 선택해야 할지 난감하다. 이럴 때 수족관과 동물원이 한 공간에 있다면 얼마나 좋을까? 이런 부모들의 마음을 헤아려 수족관과 동물원을 한 공간에 마련한 아쿠아리움이 있다. 지난 4월에 개장한 '한화 아쿠아플라넷 일산'이다. 아쿠아플라넷 일산은 국내에서 해양생물을 관람할 수 있는 63씨월드, 코엑스 아쿠아리움, 제주, 여수에 이어 다섯 번째지만 동물원과 수족관이 결합된 단일시설로는 국내 최초이며, 수도권 최대 규모의 아쿠아리움이다. 해양생물을 관람하려면 서울로 와야 하는 수도권 이북지역의 관람객을 겨냥했으며 호수공원, 국제전시단지, 한류월드로 이어지는 매머드급 접객시설이 밀집되어 있고 일산 킨텍스, 주엽역과 일산 꽃박람회장까지 연결되는 접근성이 뛰어나 전시단지의 상징적인 랜드마크로서 자리잡을 전망이다.

• Explosives and Blasting
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• v.39 no.3
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• pp.24-34
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• 2021

Electronic detonators are widely used in various construction sites due to accurate delay time. Including the cases with exceeded noise and vibration from site using electric/non-electric detonator, electronic detonators are used to improve blast fragmentation or to reduce the cost of secondary partial blasting. Furthermore, the number of cases using electronic detonators are increased for reduction of the cost and construction period by maximizing operations efficiency. This case study is about applying electronic detonators on large section station, tunnel construction site which is the part of urban area GTX A project. Although it was initially planned to utilize non-electric detonators, damage was inflicted on safety-thing. We have considered blasting method using electronic detonators as solution of this problem. By applying electronic detonators, we not only satisfied environmental regulations but also prevented nearby safety-thing from getting damaged. In addition, we were able to shorten the construction period than the initial plan by conducting single simultaneous blasting on large section station, in order to ensure safe and efficient construction.

• Journal of the Korea Institute of Construction Safety
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• v.1 no.1
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• pp.40-46
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• 2018

Only one person should be responsible for many area of works at a small construction sites with less than contract amount of USD 0.3 million. therefore, he can not be an expert in one area. Actually, this kind of small projects are not controlled by the Government because those small size of projects are exempted in following the Government control, due to certain level of small size. The above reason makes those small projects loose with an aspect of safety management without safety consciousness and safety management. The Government makes his effort to decrease nationally accident occurrences but there is considerably deep limitation to achieve a certain level of goal despite a fact that there have been more than 100 workers died annually. It is expected that some proposed management ideas technique with behavior-based safety management can be contributed to decreasing accidents at small construction sites.

• Explosives and Blasting
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• v.39 no.2
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• pp.15-26
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• 2021

Domestic electronic detonators are used widely in many quarry and construction sites since its launch at 2013. In the case of SOC projects conducted in the city, most of them are designed in high-depth to reduce complaints. The high-depth excavation needs a long construction period and huge cost for building shaft and ventilation hole. Mechanical excavation method is applied when safety things are located nearby the site. Solidity of rock and machine's performance affect on the method's efficiency. So as the efficiency is getting lower, the construction period is extended, and the cost is increases as well. This case study is about changing the machine excavation method to the blasting method which is electronic detonator applied at the shaft construction site in the city. This is an example of using electronic detonators on the construction site in reducing blast-noise and vibration while meeting environmental regulatory standards.

• Journal of the Korean Geotechnical Society
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• v.24 no.11
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• pp.55-60
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• 2008

This paper presents how the load transfer mechanism of the ground anchor affects on the stability analysis of anchored slope. The finite element analysis and the conventional limit equilibrium analysis on the anchored slope were performed and compared. The limit equilibrium analysis of the anchored slope is widely used in design practice due to the easiness of the analysis. However, the load transfer mechanism is not considered properly for the analysis. When the failure surface passes through the bonded length of an anchor, the anchor load is disregarded and the factor of safety for the anchored slope is smaller than it should be. In this study, the load transfer distribution was incorporated into the limit equilibrium stability analysis of the anchored slope and the results were compared with those of finite element analysis.

• Bulletin of Korea Environmental Preservation Association
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• s.401
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• pp.32-35
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• 2012

인간과 자연이 공존하는 환경 토피아 건설의 주역이 되고자 시종일관 노력하여 1996년 설립 이후 16년의 역사 속에서도 LG, 현대기아차, 삼성, GS칼텍스, 한화 등 대기업으로부터 인정받는 기업으로 자리 매김하게 되었다. 가족과 같은 사내분위기 속에서 경험 많은 기술진과 패기의 도전정신으로 무장한 젊은 연구진들이 혼연일체가 되어 보람이라는 울타리 속에서 성장해 나가고 있다. 주요 추진 사업으로써, 소각로 및 폐기물 재활용 기술 및 신재생에너지 관련 기술을 산 학 연 컨소시엄을 통한 지속적인 개발을 하고 있으며, 특히 소각로 화격자효율 향상을 위한 신기술 접목, 폐기물 에너지화 기술개발, 고형연료생신기술개발 음식물처리시설 기술개발 등을 중점적으로 진행하고 있다.

• Air Cleaning Technology
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• v.15 no.1 s.56
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• pp.85-86
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• 2002

국제 실내공기질 및 기후학회는 5차 IAQ`90 학술대회(토론토)를 마친 이후 1992년 109명의 과학자와 기술자에 의하여 결성되었으며 현재 핀란드에 사무국을 두고 있다. ISIAQ는 건강하고 쾌적하며 생산성 향상을 위한 실내환경 창조를 위하여 설립된 독립적인 과학 학제간 국제 비영리 기구로서, 실내공기질 및 기후에 관한 과학기술을 발전시킴으로써 실내환경설계, 건설, 유지관리, 공기질 측정과 건강과학의 증진을 목적으로 하고 있다.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.33-45
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• 2004

목적 : 21세기형 환경 친화적인 고도정수처리기술, 제균, 제탁, 소득부산물 저감 위한 최적기술로 각광받는 기술, 기존 정수처리공정과의 경제성 비교 및 막 운영관리 기술축적. 참여 5개 대표업체 : 데그레몽(프랑스 : Aquasouce 막), 대우건설(일본 : Asahikasei 막), 태영(미국 : US Filter 침지막), 비룡(일본 : Toray 막), 한화(캐나다 : Zeeweed 침지막)(중략)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6C
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• pp.331-338
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• 2008

Soil nailing is used as a method of slope stabilization and excavation support. The design method of soil nail are based on experience or assumption of interaction between soil and reinforcement. Most design methods simply considers the tension of reinforcement for analysis of slope stabilization. Soil nails interact with soils under combined loading of shear and tension. Jewell & Pedley suggested a design equation of shear force with bending stiffness and discussed that the magnitude of the maximum shear force is small in comparison with the maximum axal force. However, they have used a very conservative limiting bearing stress on nails. This paper discusses that the shear strength of soil nails should not be disregarded with proper bearing stresses on nails. The modified FHWA design method was proposed by considering shear forces on nails with bending stiffness.