• 한국항행학회논문지
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• 제27권3호
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• pp.274-280
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• 2023

Fix-to-Fix 항법은 항공기 조종사가 항행 중 현재 지점에서 원하는 특정 지점으로 이동할 때 예상 Heading을 구하기 위해 사용하는 방법이다. 하지만 이 항법은 경험에 의한 주먹구구식 방법에 기반을 두고 있기 때문에 대략적인 방향만 알 수 있을 뿐 정확한 값을 알 수는 없다. 게다가 원하는 지점에 가까워져 Radial차가 작아져 HSI상의 Bearing Pointer와 Course Indicator가 인접하게 되면, 이 방법조차 사용하기 까다로워 예상 Heading은 더욱 구하기 어렵게 된다. 이러한 한계를 해결하기 위해 삼각함수의 극한을 Fix-to-Fix 항법에 도입하였다. 본 논문에서는 Fix-to-Fix 항법을 할 때 이러한 한계를 보완할 수 있는, 삼각함수의 극한을 활용한 두 가지 방법을 제시하고 그 오차를 분석하였다.

• 한국항공우주학회지
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• 제45권1호
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• pp.79-84
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• 2017

본 연구는 미래 성장산업으로 각광을 받고 있는 무인비행장치 교육훈련 및 조종자격증명제도 개선방안을 항공선진국의 사례와 전문가 인터뷰를 통하여 제시하였다. 개선방안으로 무인비행장치 조종사에 대한 명확한 개념의 정립, 무인비행장치 자격증명 및 자격증명 유지를 위한 제도시행, 자격증명 취득을 위한 표준교재 개발과 보급, 모의비행장치 인증기준 마련 등을 제시하였다.

• 대한인간공학회지
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• 제21권1호
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• pp.1-14
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• 2002

The main purpose of this paper is to present selection criteria for ROK Airforce pilot training candidates in order to save costs involved in sequential pilot training. We use classification models such Decision Tree, Logistic Regression and Neural Network based on aptitude test results of 288 ROK Air Force applicants in 1994-1996. Different models are compared in terms of classification accuracy, ROC and Lift-value. Neural network is evaluated as the best model for each sequential flight test result while Logistic regression model outperforms the rest of them for discriminating the last flight test result. Therefore we suggest a pilot selection criterion based on this logistic regression. Overall. we find that the factors such as Attention Sharing, Speed Tracking, Machine Comprehension and Instrument Reading Ability having significant effects on the flight results. We expect that the use of our criteria can increase the effectiveness of flight resources.

• 산업공학
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• 제20권1호
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• pp.41-48
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• 2007

The main purpose of this paper is cost reduction in absurd pilot positive expense and human accident prevention which is caused by in the pilot selection process. We use classification models such as logistic regression, decision tree, and neural network based on aptitude test results of 505 ROK Air Force applicants in 2001~2004. First, we determine the reliability and propriety against the aptitude test system which has been improved. Based on this conference flight simulator test item was compared to the new aptitude test item in order to make additional yes or no decision from different models in terms of classification accuracy, ROC and Response Threshold side. Decision tree was selected as the most efficient for each sequential flight training result and the last flight training results predict excellent. Therefore, we propose that the standard of pilot selection be adopted by the decision tree and it presents in the aptitude test item which is new a conference flight simulator test.

• 대한인간공학회지
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• 제16권2호
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• pp.83-100
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• 1997

The Human Sensory Feedback Laboratory, park of the Armstrong Laboratory at Wright-Patterson Air Force Base, Ohio, is involved in the development and evaluation of systems that provide sensory feedback to the human operator in telerobotic and virtual environment applications. Specific projects underway in the laboratory are primarily concerned with the information provided by force and vibrotactile feedback to the operator in dextrous manipulation tasks. Four specific research projects are described in the present report. These include : 1) experiments evaluating a 30-element fingertip display, which employs a titanium-nickel shape memory alloy actuator design to provide vibrotactile feedback about object shape and surface texture ; 2) of a fingertip force-feedback display for 3-dimensional information about object shape and suface texture ; 3) use of a force- feedback joystic to provide "force tunnel" information in pilot pursuit tracking tasks ; and 4) evaluations of a 7 degree-of-freedom exoskeleton used to control a robotic arm. Both basic and applied research questions are discussed.

• Membrane and Water Treatment
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• 제9권1호
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• pp.43-51
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• 2018

Hollow fiber (HF) membranes are gaining wide interest over flat membranes due to their compaction and high area to surface volume ratio. This work addresses the fabrication of HF from polysulfone (PS) and polyethersulfone (PES) using N-methylpyrrolidone (NMP) as solvent in addition to other additives to achieve desired characteristics. The semi-pilot spinning system includes jacketed vessel, four spinneret block, coagulation and washing baths in addition to dryer and winder. Different parameters affecting dry-wet spinning phase inversion process were investigated. Dope compositions of PES, NMP and polyvinyl pyrrolidone (PVP) of varying molecular weights as additive were addressed. Some critical parameters of importance were also investigated. Those include dope flow rate, air gap, coagulation & washing baths and drying temperatures. The measured dope viscosity was in the range from 1.7 to 36.5 Pa.s. Air gap distance was adjusted from 20 to 45 cm and coagulation bath temperature from 20 to $46^{\circ}C$. The HF membranes were characterized by scanning electron microscope (SEM), atomic force microscope (AFM) and mechanical properties. Results indicated prevalence of finger like structure and average surface roughness from about 29 to 78.3 nm. Profile of stress strain characteristics revealed suitability of the fibers for downstream interventions for fabrication of thin film composite membrane. Different empirical correlations were formulated which enable deeper understanding of the interaction of the above mentioned variables. Data of pure water permeability (PWP) confirmed that the fabricated samples fall within the microfiltration (MF)-ultrafiltration (UF) range of membrane separation.

• 드라이브 ㆍ 컨트롤
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• 제14권4호
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• pp.17-22
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• 2017

In this study, the back-drivability of the single-rod and double-rod type EHAs (Electro-Hydrostatic Actuators) was compared by computer simulation and experiments. The back-drivability of EHAs exhibit non-linear behavior like their force tracking performance. In case of the double-rod type EHA, the back-drivability was mostly influenced by the bulk modulus of oil that changes with the working pressure due to entrapped air. The back-drivability of the single-rod type EHA was directly affected by the operation states of its pilot-operated check valves, while the asymmetrical piston geometry and the non-linear bulk modulus of oil also made the dynamic response in building up the cylinder pressure dependent on the operating conditions.

• 한국항공운항학회지
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• 제20권1호
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• pp.1-12
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• 2012

Many pilots of the Korean Air Force(ROKAF) leave their jobs in order to move out to civilian airlines. Thanks to this considerable turnover phenomenon, the ROKAF faces a serious lack of air defense power. While the common understanding of this problem mainly talks about 'money' as the main cause of turnover, some pilots point out rather different issues. Many pilots say in a large-scale survey that they face serious job stresses not only from relative shortage of their income compared to civilian pilots, camp life, separated family conditions, overly loaded administrative works, but also from their professional flight trainings and low promotion rate to high ranks. The survey shows, however, at the same time, that the ROKAF pilots do not consider their job trainings and overall roles as the military pilots as the main factor causing the intention to turnover. A critical aspect of the pilots' job condition is many stress factors consistently affect overall job satisfaction level which stimulates the decision to turnover when they have to choose between the extension of military service as a pilot and moving-out to civilian airlines for new pilot's life. In other words, they accept the job difficulties as pilot in the military, but their long-term job satisfaction level is negatively affected by the job stresses.

• 한국의류산업학회지
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• 제11권5호
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• pp.764-770
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• 2009

This study was conducted to analyze the wearing condition on gloves for pilots and to suggest the developments for pilot gloves design. This survey was performed with 99 pilots and the questionnaires included items about discomfort, materials and problems when wearing pilot gloves. The respondents felt uncomfortable on the finger tip, the hollow area of the hand and the end of thumb when they move their hands with the gloves. They replied that the finger length, palm length, and circumference of the fingers did not match well. Also they complained there was severe abrasion in the tip of the thumb, finger tips and the middle of the palm of the gloves. The result of these analyses supports the following suggestions. It is necessary to improve durability by applying the additional materials to the severely worn parts. Punching on the glove materials could improve sweat rate and ventilation, and careful washing should be accompanied to prevent the occurrence of linters and transformation after laundering. And it is needed to prepare an accurate and more diversified size system and to design the gloves fitted to the individual hands. With these in mind, it is required to propose solutions for pilot gloves with reference to the survey results in order to design appropriate pilot gloves in terms of movement, size and material. It was concluded that an analysis of the wearing condition and developments are useful for ergonomics pilot gloves design.

• 한국항공운항학회지
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• 제19권4호
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• pp.99-104
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• 2011

Pilots are exposed to carcinogenic substances like radiation, ozone, exhaust gas from jet engine, and electromagnetic wave, their environment can be very hazardous. I designed this study to know if there is any difference between pilots and general people in cancer incidence. I analyzed cancer cases between 1999 and 2008, and investigated their age, site, aircraft types, and sex. I compared pilot's cancer incidence with general people during same periods. Statistical analysis was performed with standardized incidence ratio (SIR). 10 cases were high performance pilots, 5 cases were low performance pilots. The average age when the diagnosis had been made was $39{\pm}7.8$. Pilot's incidence ratio was lower than people's, the most common cancer was kidney, and there was no lung cancer. Cancer is influenced by gene and environment, each country has different patterns. The low incidence ratio in Korean pilots might be due to "healthy worker effect". I think we should perform further investigation on kidney cancer.