• Management Science and Financial Engineering
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• v.10 no.2
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• pp.73-87
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• 2004

Automotive and aircraft assembly process rely on fixtures to support and coordinate parts and subassemblies. Fixture layout in multi-station panel assemblies has a direct dimensional effect on final products and thus presents a quality problem. This paper describes a methodology for fixture layout design in multi -station assembly processes. An optimal fixture layout improves the robustness of a fixture system against environmental noises, reduces product variability, and eventually leads to manufacturing cost reduction. One of the difficulties raised by multi-station fixture layout design is the overwhelmingly large number of design alternatives. This makes it difficult to find a global optimality and, if an inefficient algorithm is used, may require prohibitive computing time. In this paper, simulated annealing is adopted and appropriate parameters are selected to find good fixture layouts. A four-station assembly process for a sport utility vehicle (SUV) side frame is used throughout the paper to illustrate the efficiency and effectiveness of this methodology.

• Aerospace Engineering and Technology
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• v.7 no.2
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• pp.38-45
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• 2008

It is challenging to build the integrated information system for a large scale cooperative R & D project. To develop the aircraft program which especially has several leading agencies and is supported by many demestic/foreign participating companies, the common data flow in harmony is the core factor to achieve a development goal. For this, the development are carried out maintaining the existing management systems of agencies and companies. As a first step, the standard for the common data information and the classification category of technical data are defined. Second, the work flow standards are also set. Based on the foundation, the efficient technical data management system are built including the function of storage, inquiry, revision, link, approval, submission, etc.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.685-688
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• 2005

In this study, an efficient algorithm for the numerical search of the geodesic path of the creeping wave on a doubly curved surface is developed. The ellipsoid as a doubly curved surface is studied because of its three dimensional nature in that it can be used to simulate the body of an aircraft, or a missile body. Numerical result of the geodesic path on an ellipsoid is given.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.1
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• pp.108-113
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• 2014

Recently increase in the number of aircraft caused the air traffic congestion and flight delays. If timely action to reform the air traffic system is not taken, these may result in added economic impact. As a result, the air traffic management should be changed in an innovative manner to modernize the existing air traffic control environment. This paper reviews the trends of airspace reforms such as integration of terminal control areas and flexible use of airspace introduced by foreign countries and compares their merits and demerits in order to provide a judgement to adopt the concept in domestic airspace in the future.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.7 no.1
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• pp.77-89
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• 1999

The atmosphere condition at Kimpo International Airport occasionally prevents the aircraft from landing and forces them to fly to an alternate airport, especially in October and November during a year. Many airlines designated foreign airports instead of Korean airports as alternate airports in the case of the bad weather condition preventing use of Kimpo Airport. This paper addresses 1) economic comparison of candidates for the alternate airport, 2) what are the criteria for the alternate airport selection and the relative importance among the criteria and 3) evaluation of candidates for alternate airport using Brown and Gibson's pair-wise comparison method. It is found to be possible to reduce costs related alternate flight by 36% using Korean airports rather than using Japan's Hukuoka Airport. However, airlines weigh more on the factors such as service level of ground handling, accommodation for passengers and ground access convenience than costs. Among Korean airports, Kimhae International Airport is found the most favorable airport as the alternate airport for Kimpo International Airport.

• Journal of Aerospace System Engineering
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• v.15 no.5
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• pp.24-32
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• 2021

Personal Air Vehicle (PAV), Cargo UAS (Cargo UAS), and existing manned and unmanned aircraft are key vehicles for urban air mobility (UAM), and should demonstrate compatibility for the design of aircraft systems. The safety assessment required by for certification to ensure safety and reliability should be systematically performed throughout the entire cycle from the beginning of the aircraft development process. However, with the increasing complexity of safety critical aviation systems and the application of state-of-the-art systems, conventional experience-based and procedural-based safety evaluation methods make ir difficult to objectively assess safety requirements and system safety. Therefore, Model-Based Safety Assessment (MBSA) using modeling and simulation techniques is actively being studied at domestic and foreign countries to address these problems. In this paper, we propose a Model-Based Safety Evaluation framework utilizing modeling and simulation-based integrated flight simulators. Our case studies on the Traffic Collision Availability System (TCAS) and Wheel Brake System (WBS) confirmed that they are practical for future safety assessments.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.193-197
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• 2002

Polyurethane casting wing fairings included in F-5E/F 15% spar kit are to be installed on aircraft wing surfaces and used for compensating the changes of the aerodynamic configuration by the leading edge extension fairings. These fairing are mandatory items in repairing wing areas and was imported from foreign supplier with long term delivery and high cost. Accordingly, local manufacturing is necessary to get rid of above disadvantages such as long term delivery and high cost. Basic properties test of specimen to be developed and part's requirements after localization was taken and its values were similar or higher when comparing with the original's even in low temp test at -55C. Casting mold process was used to manufacture the polyurethane fairings and its demensional stability ＆ physical condition was proper and met to the related specification and drawing's requirements

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.2
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• pp.26-31
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• 2012

A new operational concept for the CNS/ATM using the digital data communication technology and satellite navigation system is being implemented globally and the United States is the first country to apply UAT ADS-B system for general aviation. Korea also has plan to build ADS-B system for aeronautical surveillance to monitor low altitude flight of light aircraft and ultra-light flying device and the research to develop UAT ADS-B equipment is being carried out. This paper presents the application method of UAT ADS-B to support test operation with case study of foreign UAT ADS-B operation and survey of domestic environment.

• Journal of Aerospace System Engineering
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• v.15 no.3
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• pp.93-98
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• 2021

In Europe, it is necessary to fulfil the type certification criteria by the European Aviation Safety Agency (EASA) when developing an aircraft engine. According to type certification criteria, a 150 hours endurance test should be performed to verify the stability of the engine structure under the engine's operating limit conditions. The type certification criteria for the 150 hour endurance test are specified in JAR-E, which is the EASA type certification. Currently, the Arriel 2L2 engine is being developed in cooperation with a foreign manufacturer, and a 150 hours endurance test was performed. In this study, a 150 hours endurance test procedure is conducted in consideration of the operation characteristics of the currently developed engine.

• Journal of Aerospace System Engineering
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• v.17 no.1
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• pp.33-41
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• 2023

As seen in the case of the Boeing 737 Max accident, the proportion of aircraft software is rapidly increasing. However, it is vulnerable to safety issues. In case of domestic aircraft software, to operate a Light Unmanned Aerial Vehicle (LUAV) less than an empty weight of 150 kg, safety certification is required for an Ultra-Light Vehicle (ULV). However, software certification procedure is not included. Since the use of LUAVs has increased recently, software verification is required. This paper proposed a checklist of LUAV software that could be applied to LUAV referring DO-178C, an aviation software certification standard. A case study of applying the proposed checklist to the Model-based Development-based Helicopter Flight Control Computer (FCC) project currently used by domestic and foreign advanced companies and institutions was conducted.