• 한국물환경학회지
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• 제21권2호
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• pp.132-140
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• 2005

The pilot test of a new alternative for small wastewater treatment system has been conducted for two years. It consists of a hybrid bioreactor and the expert system including the process control logic, PLC system, and HMI for the process automation. In order to monitor and remote control its status, the real-time data was transferred from the on-site control center to the central station via a wireless local area network. More efficient and stable performances were observed at automatic operating mode compared with the manual. On an average, COD, SS, T-N and T-P concentrations in the effluent from the hybrid bioreactor were less than 14, 7, 12 and 0.9 mg/L, respectively. According to the result from pilot tests, the quality of treated wastewater with sand filtration was enough to be utilized again.

• International Journal of Aeronautical and Space Sciences
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• 제5권1호
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• pp.57-63
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• 2004

UAV(Unmanned Aerial Vehicle) has become one of the most popularmilitary/commercial aerial robots in the new millennium. In spite of all theadvantages that UAVs inherently have, it is not an easv job to develop a UAVbecause it requires very systematic and complete approaches in full developmentenvelop. The ground test and evaluation phase has the utmost importance in thesense that a well-developed system can be best verified on the ground. In addition,many of the aircraft crashes in the flight tests were resulted from the incompletedevelopment procedure. In this research, a verification procedure of the wholeairbome integrated system was conducted including the flight management system.An airbome flight control computer(FCC) senses the extemal environment from thepehpheral devices and sends the control signal to the actuating system using theassigned control logic and flight test strategy. A ground test station controls themission during the test while the downlink data are transferred from the flightmanagement computer using the serial communication interface. The pilot controlbox also applies additional manual actuating commands. The whole system wastested/verified on the wind-tunnel system, which gave a good pitch controlperformance with a preUspecified flight test procedure. The ground test systemguarantees the performance of fundamental functions of airbome electronic systemfor the future flight tests.

• 공업화학
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• 제20권5호
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• pp.557-560
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• 2009

본 연구에서는 글라스를 $100{\mu}m$ 이하의 두께로 박판화하기 위한 새로운 습식 에칭방법 및 에칭 용액을 검토하였다. $NH_4F$ 또는 $NH_4HF_2$를 주성분으로 황산 또는 질산을 첨가한 경우 에칭 용액의 불산 함유량을 저감하는 데에 효과가 있었다. 혼산 용액의 조성과 온도의 영향을 검토하였으며, 음이온계 계면활성제의 첨가는 에칭반응에 의해 생성되는 슬러지의 부착을 억제해주는 효과가 있었다. 수류 발생부를 가지는 새로운 파일럿 장비를 사용하여 상용 무알칼리 글라스와 소다라임 글라스의 에칭 실험을 실시하였다. $640{\mu}m$ 두께의 무알칼리 글라스를 $45{\mu}m$ 두께로 $500{\mu}m$ 두께의 소다라임 글라스를 $100{\mu}m$ 두께로 박판화하였으며, 에칭 후의 표면 조도는 $0.01{\sim}0.02{\mu}m$를 유지하였다.

• 한국양식학회지
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• 제21권3호
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• pp.125-132
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• 2008

Seed production of olive flounder Paralichthys olivaceus was performed in a pilot RAS. The growth of juvenile olive flounder and changes in water quality were monitored for the entire production period. The pilot RAS consisted of 8 circular culture tanks($4.0mD{\times}1.0mH$), 2 trickling biofilters($1.7mD{\times}2.0mH$), 2 protein skimmers ($0.8mD{\times}2.5mH$), and 4 sedimentation chambers($0.7mD{\times}1.5mH$). The culture surface area was about $100.5m^2$ and the actual working volume was about $106.9m^3$. As many as 300,000 fertilized olive flounder eggs were initially distributed into 2 culture tanks with the water temperature at $19.0^{\circ}C$. Live feeds such as rotifers and Artemia nauplii were fed until the 32nd day after hatching, and a commercial diet was fed from the 19th day to the end of the experiment. After 70 days, 150,256 juveniles with a body length of $65.8{\pm}3.9mm$ were produced in the RAS, with a daily growth rate for body length of 4.7%/day. At this time, the final culture density was 1,495 individuals $m^{-2}$, and 13.6 L of makeup water, 0.071 kW of electricity and 0.025 L of diesel fuel were used to produce a juvenile olive flounder. During metamorphosis of the larvae, the TAN concentration increased to 0.99 mg/L, which made the larvae sensitive to result in some mortality. However no more massive mortality occurred at the juvenile stage after metamorphosis even at a TAN concentration of 4.25 mg/L and a ${NO_2}^{-}-N$ concentration of 2.45 mg/L.

• Korean Chemical Engineering Research
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• 제58권1호
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• pp.150-162
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• 2020

The proprietary post-combustion CO₂ solvent (KoSol) developed by the Korea Electric Power Research Institute (KEPRI) was applied at the Shanghai Shidongkou CO₂ Capture Pilot Plant (China Huaneng CERI, capacity: 120,000 ton CO₂/yr) of the China Huaneng Group (CHNG) for performance evaluation. The key results of the pilot test and data on the South Korean/Chinese electric power market were used to calculate the predicted cost of CO₂ avoided upon deployment of CO₂ capture technology in commercial-scale coal-fired power plants. Sensitivity analysis was performed for the key factors. It is estimated that, in the case of South Korea, the calculated cost of CO₂ avoided for an 960 MW ultra-supercritical (USC) coal-fired power plant is approximately 35~44 USD/tCO₂ (excluding CO₂ transportation and storage costs). Conversely, applying the same technology to a 1,000 MW USC coal-fired power plant in Shanghai, China, results in a slightly lower cost (32~42 USD/tCO₂). This study confirms the importance of international cooperation that takes into consideration the geographical locations and the performance of CO₂ capture technology for the involved countries in the process of advancing the economic efficiency of large-scale CCS technology aimed to reduce greenhouse gases

• 한국조경학회지
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• 제31권3호
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• pp.74-82
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• 2003

Under the assumption that the temperature of one location is closely related to land use characteristics around that location, this study is carried out to assess the impact of urban land use patterns on air temperature. In order to investigate the relationship, GIS techniques and statistical analyses are utilized, after spatially connecting urban land use data in Seoul Metropolitan Area with atmospheric data observed at Automatic Weather Stations (AWS). The research method is as follows: (1) To find out important land use factors on temperature, simple linear regressions for a specific time period (pilot study) are conducted with urban land use characteristics, (2) To make a final model, multiple regressions are carried out with those factors and, (3) To verify that the final model could be appled to explain temperature variations beyond the period, the model is extensively used for 5 different time periods: 1999 as a whole; summer in 1999; 1998 as a whole; summer in 1998; August in 1998. The results of simple linear regression models in the pilot study show that transportation facilities and open space area are very influential on urban air temperature variations, which explain 66 and 61 percent of the variations, respectively. However, the other land use variables (residential, commercial, and mixed land use) are found to have weak or insignificant relationship to the air temperatures. Multiple linear regression with the two important variables in the pilot study is estimated, which shows that the model explains 75 percent of the variability in air temperatures with correct signs of regression coefficients. Thus, it is empirically shown that an increase in open space and a decrease in transportation facilities area can leads to the decrease in air temperature. After the final model is extensively applied to the 5 different time periods, the estimated models explain 68 ∼ 75 percent of the variations in the temperatures is significant regression coefficients for all explanatory variables. This result provides a possibility that one air temperature model for a specific time period could be a good model for other time periods near to the period. The important implications of this result to lessen high air temperature we: (1) to expand and to conserve open space and (2) to control transportation-related factors such as transportation facilities area, road pavement and traffic congestion.

• 한국항행학회논문지
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• 제25권1호
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• pp.52-59
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• 2021

IATA (International Air Transport Assosiation)의 운송용 항공기 사고 집계에 의하면, 사고 건의 61%가 비행의 접근 및 착륙단계에서 발생 되었으며, 이중 항공기의 불안정한 접근으로 인한 사고가 16%인 것으로 파악되었다. 이는 조종사의 불안정한 접근 및 수정 조작 미흡에 따른 복행을 시행하지 않고, 무리하게 접근을 지속하여 사고로 이어진 것으로 식별되었다. 불안정 접근의 원인으로는 공항의 접근 절차, 조종사의 실수, 잘못된 계획, 업무 부하 (workload), ATC (Air Traffic Control) 혼잡 등 다양하게 있을 수 있다. 본 연구에서는 비행 데이터 분석 시스템을 활용하여, 불안정 접근 이벤트가 반복해서 발생하는 국내의 사례 공항과 기종을 선정하여, 주요 발생 이벤트, 공항 접근 절차, 조종사의 조작 뿐만이 아니라 공항의 기상, 지리적 여건 등 다양한 환경적 요인을 포함한 비행 데이터 분석을 통해 불안정 접근 이벤트의 경향성과 발생 원인 및 위험 요소를 식별하고 제거하여 불안정 접근 이벤트의 경감조치 및 항행 안전 증진 방안 마련의 시사점을 도출하고자 한다.

• The Plant Pathology Journal
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• 제33권3호
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• pp.337-344
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• 2017

To develop a commercial product using the mycoparasitic fungus Simplicillium lamellicola BCP, the scale-up of conidia production from a 5-l jar to a 5,000-l pilot bioreactor, optimization of the freeze-drying of the fermentation broth, and preparation of a wettable powder-type formulation were performed. Then, its disease control efficacy was evaluated against gray mold diseases of tomato and ginseng plants in field conditions. The final conidial yields of S. lamellicola BCP were $3.3{\times}10^9conidia/ml$ for a 5-l jar, $3.5{\times}10^9conidia/ml$ for a 500-l pilot vessel, and $3.1{\times}10^9conidia/ml$ for a 5,000-l pilot bioreactor. The conidial yield in the 5,000-l pilot bioreactor was comparable to that in the 5-l jar and 500-l pilot vessel. On the other hand, the highest conidial viability of 86% was obtained by the freeze-drying method using an additive combination of lactose, trehalose, soybean meal, and glycerin. Using the freeze-dried sample, a wettable powder-type formulation (active ingredient 10%; BCP-WP10) was prepared. A conidial viability of more than 50% was maintained in BCP-WP10 until 22 weeks for storage at $40^{\circ}C$. BCP-WP10 effectively suppressed the development of gray mold disease on tomato with control efficacies of 64.7% and 82.6% at 500- and 250-fold dilutions, respectively. It also reduced the incidence of gray mold on ginseng by 65.6% and 81.3% at 500- and 250-fold dilutions, respectively. The results indicated that the new microbial fungicide BCP-WP10 can be used widely to control gray mold diseases of various crops including tomato and ginseng.

• Journal of the Korean Wood Science and Technology
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• 제44권5호
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• pp.622-628
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• 2016

본 논문에서는 최근 목질계바이오매스를 원료로 한 수송용(transportation) 바이오연료의 국제적 상용화 기술의 흐름과 산업체 동향에 대하여 조사하였다. IEA, Bioenergy Task 39에서 집계한 수송용 바이오연료 관련 산업체에서 목질계 원료를 사용하는 산업체는 93개 업체였고, 그중에서 Commercial type의 산업체를 기준으로 생화학적 전환기술을 채택한 업체는 전체의 84%로 나타나 생화학적 전환공정이 목질계 바이오연료 분야의 주류 기술인 것으로 밝혀졌다. 생화학적 전환공정을 채택한 Commercial type 산업체의 주요 생산품은 바이오에탄올로서 연간 약 115만 5천 톤, 바이오오일은 약 12만 톤으로 전 세계의 수송용 연료에 혼입목표량을 대체하기에 매우 부족한 상황인 것으로 밝혀져 수송용 바이오연료 시장은 기술과 규모 면에서 기술개발과 상용화 노력이 더욱 요구됨이 시사되었다. 또한 pilot type의 산업체에서 생화학공정 및 열화학공정기술을 활용한 실험적 생산이 다수 진행되고 있어, 향후 목질계 원료에 의한 액체바이오연료 기술이 다양하게 실용화될 가능성이 큰 것으로 시사되었다.

• 멤브레인
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• 제23권4호
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• pp.257-266
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• 2013

본 연구에서는 고온에서 유기용매를 정제할 수 있는 고온, 고압에서 안정한 상업화 규모의 고효율 중공사 투과증발막, 막모듈 개발, 상업 규모의 막분리 장치시스템 개발을 수행하였는데 구성 요소기술은 1) 고온 고압 하에서 사용할 수 있는 브레이드 강화 중공사 막제조, 2) 중공사 막모듈 제조, 3) 막 탈수, 정제장치 시스템 설계 및 제작기술등을 개발하였다. 개발 중 공사 투과증발막은 독일의 슐츠막 보다 막 안정성과 막 성능이 우수하였으며, 막면적 4.6 $m^2$의 고효율 상업적 규모의 중공사막모듈을 개발하였고, 200 L/hr 이상의 처리용량의 Pilot 규모의 투과증발 막장치 시스템을 개발하였다. 기존 평막 혹은 중공사막에서 모듈에서 볼 수 있었던 모듈내부에 공급액의 dead volume형성, 공급액의 채널링 현상들을 제거하기 위해서 본 개발 중공사막과 막모듈의 특징은 고온, 고압의 유기용매를 중공사막 내부로 공급되어 흐르도록 설계되어 있어 막분리 효율이 우수하며 특히 기존의 막제품의 대비 막모듈 가격이 저렴하고, 막성능 및 치수안정성이 우수하다. 또한 공급액의 열손실 적어 에너지 효율이 우수할 뿐 아니라 막모듈 내에 중공사막 사이의 간격이 일정하여 가해주는 진공이 균일하게 각 중공사막의 투과부 표면에 전달될 수 있기 때문에 투과된 투과물을 막 표면으로부터 효과적으로 제거할 수 있으므로 투과속도 또한 우수하다.