• KSBB Journal
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• 제22권4호
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• pp.191-196
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• 2007

본 연구는 급속한 산업 발전으로 인해 일어난 많은 수질오염 문제 중 생활하수의 처리방법에 관심을 기울여 생물막 공법을 이용하였는데, 이는 소규모 오폐수 처리장치에서 운전과 유지가 간단하고 활성슬러지 공정보다 넓은 부지를 필요로 하지 않기 때문이다. 생물막 공법 중 생물여상법의 변법을 적용한 Pilot 규모의 상향류식 충전탑형 반응기로 내부의 담체로는 폐토기와 폐비닐을 넣어 혐기조와 호기조를 구성하였고, 생활 오수로는 식당 오수를 이용하여 Lab.-Scale 실험 후 Pilot-Scale로 Scale-up하여 100여일 간에 걸쳐 실험을 수행하였다. 실험은 연속 포기시 일정 HRT에서 유기물과 질소, 인 제거율을 살펴보았다. 실험결과 $BOD_5$와 SS의 평균 제거율은 각각 94.33%와 87.77%로 높은 제거율을 보였으나, $COD_{Cr}$은 81.46%로 목표 제거율 90% 이상에 미치지 못하였고, T-N과 T-P도 각각 71.92%와 21.10%로 예상보다 약간 낮았다. 특히 $COD_{Cr}$와 T-N의 제거율은 지난 Lab.-Scale 때보다 약 10% 정도의 감소를 하여 Pilot-scale에 내외적인 문제가 작용한 것으로 보였다.

• 항공우주의학회지
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• 제30권2호
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• pp.54-60
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• 2020

Pilot fatigue is a great hazard to aviation safety. In recent years, long-distance fights have been increasing and flight hours have been increasing, which has made fatigue issues important. International organizations in the aviation sectors (ICAO, FAA, IATA etc.) recommend management of fatigue within the SMS (Safety Management System) framework. A scientific and systematic approach to measuring fatigue is required as a prerequisite to preparing safety management measures for pilot's fatigue. Therefore, in this study, I would like to consider recent trends and implications for fatigue measurement. First, I aimed to consider recent the accident cases related to fatigue. Second, I also considered how to measure the pilot's fatigue. Finally, the direction of the countermeasures against fatigue through fatigue measurement was developed and suggested.

• Restorative Dentistry and Endodontics
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• 제49권1호
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• pp.3.1-3.8
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• 2024

This article is a narrative review that discusses the recommended sample size requirements to design a pilot study to assess the reliability of a questionnaire. A list of various sample size tables that are based on the kappa agreement test, intra-class correlation test and Cronbach's alpha test has been compiled together. For all calculations, type I error (alpha) was set at a maximum value of 0.05, and power was set at a minimum value of 80.0%. For the kappa agreement test, intra-class correlation test, and Cronbach's alpha test, the recommended minimum sample size requirement based on the ideal effect sizes shall be at least 15, 22, and 24 subjects respectively. By making allowances for a non-response rate of 20.0%, a minimum sample size of 30 respondents will be sufficient to assess the reliability of the questionnaire. The clear guideline of minimum sample size requirement for the pilot study to assess the reliability of a questionnaire is discussed and this will ease researchers in preparation for the pilot study. This study provides justification for a minimum requirement of a sample size of 30 respondents specifically to test the reliability of a questionnaire.

• 한국항공운항학회지
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• 제30권1호
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• pp.44-49
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• 2022

This study performed precision instrument landing procedures for pilots with a commercial pilot license using VR HMD flight simulators, and assuming that the center of the pilot's gaze is in the front, 3-D.O.F. head tracking data and 2-D eye tracking of VR HMD worn by pilots gaze tracking was performed through. After that, AOI (Area of Interesting) was set for the instrument panel and external field of view of the cockpit to analyze how the pilot's gaze was distributed before and after the decision altitude. At the same time, the landing results were analyzed using the Localizer and G/S data as the pilot's precision instrument landing flight data. As a result, the pilot was quantitatively evaluated by reflecting the gaze tracking and the resulting landing result using a VR HMD simulator.

• 한국환경보건학회지
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• 제22권4호
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• pp.10-15
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• 1996

Treatment of a synthetic wastewater was made for the purpose of evaluating the performance of a pilot scale of an IFBBR. The particles used in this experiment were circular shaped polystyrene whose density was lower than that of water. The reactor volume was 400 l and the SCOD removal efficiency was more than 90% at HRT of 5 hrs. The IFBBR was successfully operated for 5 months without any significant problems. And it whs certained that IFBBR had a potential capability for treating wastewater.

• 한국항공운항학회지
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• 제29권2호
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• pp.117-121
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• 2021

Multi-crew Pilot License (MPL) is an international pilot certification adopted by the International Civil Aviation Organization (ICAO) in 2006 under the recognition of the need for efficient and systematic pilot training including the education of pilots with advanced aviation technology and ability to respond to flight environment, resolution of the human factor problems of pilots, and provision of stable training tools for transport aircraft pilots for potential risk of pilot shortage in the future. South Korea also has prepared a legal basis for operating an MPL system in the Aviation Act in 2009, but there has been no domestic MPL qualifier. The biggest reason for this seems to be the insufficient domestic MPL training system. Therefore, it is necessary to benchmark the international standards of the ICAO, and to promote the development of the Korean MPL training system through revision and supplementation of laws and regulations in consideration of Korean circumstances.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.154-154
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• 2017

• 동력기계공학회지
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• 제17권6호
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• pp.18-24
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• 2013

An experimental study was performed to investigate the characteristics of combustion pressure and exhaust emissions when the pilot injection timing and EGR rate were changed in a CRDI 4-cylinder diesel engine. The pilot injection timing and EGR rate have a significant impact on the combustion and emission characteristics of diesel engine. In this study, the pilot injection timing and EGR rate variation were conducted to 2000rpm of engine speed with torque 50Nm. Combustion pressure and heat release rate were decreased under high EGR rate conditions but increased under the pilot injection timing $20^{\circ}$(BTDC). IMEP and the maximum pressure in cylinder(Pmax) were decreased under the same injection timing with the increase of EGR rate. The NOx emission was decreased with increasing the EGR rate. On the other hand, in the same injection timing conditions, CO, HC, $CO_2$ emissions were increased with increasing the EGR rate.

• 한국연소학회지
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• 제20권4호
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• pp.19-25
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• 2015

An experimental study was conducted to find the effect of a pilot flame on the flammability of inert-gas-diluted methane and propane. The diffusion pilot flame was formed with propane at the innermost nozzle of a concentric triple co-flow burner. The main diffusion flame was formed with nitrogen-diluted methane or propane at the outermost nozzle of the burner. An air flow was located in-between. The results showed that the existence of the pilot flame helped stabilizing the main flame even at the flammability limit concentration of nitrogen-diluted fuel. The co-flow burner generated re-circulation zones and local variation of equivalence ratio depending on the flow rates of the reactants, which are known to help flame stabilization. Hot-wire experiments confirmed that both heating of the reactants and supplying of active chemical species by the pilot flame contributed to stabilization of the main flame. The results of this study would suggest a design concept for an efficient SVRU system that minimizes the emission of unburned hydrocarbon fuel from ship fuel tanks.

• The Journal of Asian Finance, Economics and Business
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• 제9권7호
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• pp.41-52
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• 2022

This paper analyzes the advantages and opportunities of regional development prospects of the China (Anhui) Pilot Free Trade Zone. In addition, it provides suggestions for the future development of the Anhui Pilot Free Trade Zone. The establishment of the Anhui Pilot Free Trade Zone is a major platform for Anhui Province, China, to serve the nation's opening-up strategy to the world and an opportunity for the Anhui region to enhance the level of an open economy. The development plan points out that the Anhui Pilot Free Trade Zone 1) takes institutional innovation as the core, 2) complies with the requirements of the innovation-driven development and promotion of the Yangtze River Delta regional integration development strategy, and 3) plays a vital node role in promoting the construction of the Belt and Road Initiative, and 4) accelerates the construction of scientific and technological innovation sources, advanced manufacturing and strategic emerging industries. The findings of this study highlight three critical achievements as follows: 1) optimization and improvement of the business environment have progressed, 2) the conversion rate of scientific and technological innovation achievements has increased, and 3) advanced high-tech manufacturing and strategic emerging industries are clustered and developed.