• Journal of Biomedical Engineering Research
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• v.24 no.2
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• pp.77-82
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• 2003

Virtual colonoscopy is a non-invasive computerized procedure to detect polyps by examining the colon from a CT data set. To fly through the inside of colons. the extraction of a suitable flight-path is necessary to Provide the viewpoint and view direction of a virtual camera. However. manual path extraction by Picking Points is a very time-consuming and difficult task due 1,c, the long and complex shape of colon. Also, existing automatic methods are computationally complex. and tend to generate an improper and/or discontinuous path for complicated regions. In this paper, we propose a fast flight-path generation algorithm using the distance and order maps. The order map Provides all Possible directions of a path. The distance map assigns the Euclidean distance value from each inside voxel to the nearest background voxel. By jointly using these two maps. we can obtain a proper centerline regardless of thickness and curvature of an object. Also, we Propose a simple smoothing technique that guarantees not to collide with the surface of an object. The phantom and real colon data are used for experiments. Experimental results show that for a set of human colon data, the proposed algorithm can provide a smoothened and connected flight-path within a minute on an 800MHz PC. And it is proved that the obtained flight-Path provides successive volume-rendered images satisfactory for virtual navigation.

• Science of Emotion and Sensibility
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• v.26 no.1
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• pp.65-78
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• 2023

Aircraft are representative of human-machine systems. There is a delay between the human operation and the completion of the machine operation such as when the machine starts to operate and when the force is transmitted to the machine and completed. Time perception is an important component of timing tasks and is known to be affected by the anxiety associated with high arousal. This research verified the impact of weather, flight, and time conditions on the anxiety and time perception of in-service pilots in a virtual reality area. Weather conditions were divided into visual flight weather conditions and very low visibility conditions. Experiments 1 and 2 were performed with different flight and time conditions. In Experiment 1, time perception was measured by employing a button added to the control rod in the scenario of hovering and level flight with relatively little transformed in momentum and little delay. In Experiment 2, time perception was measured in the procedure of naturally taking off the helicopter by employing only the control stick in a takeoff scenario where there was a lot of transformation in momentum and a lot of delays. As a result of the experiment, it was reported that anxiety and heart rate increased in very low visibility conditions In particular, among all flight conditions in Experiments 1 and 2, it was reported that time was overestimated in the scenario of increased anxiety. This outcome can lead to overestimation of time under the impact of anxiety and failure of the timing task, which may lead to challenges in maneuvering and possibly lead to accidents.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.237-246
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• 2020

The background of the research is the following: As a result of ultra-light flying device industry development, the utilization of drones and their efficiency have been increasing. However, problems regarding flight permission·approval procedure have not been improved, resulting in increased number of civil complaints. Thus, the purpose of this research is to minimize such civil petition according to the required standards of the two government organizations through enhancing the procedure for managing and employing the system. The research methods entail pinpointing the problems by analysing ultra-light flying device related literature review and by holding focus-interviews with field experts, thereby verifying and providing improved solutions. Under (MLIT) Ministry of Land, Infrastructure and Transport supervision and in accordance with aviation security law, the research provides various updated functions such as improved civil petition processing system's employment and management system, flight approval, integration of names, process, format regarding aviation photographing approval, tool buttons such as the 'Main' button in the system's homepage. This research has the following expected effects : Firstly in the law and regulations section, the clear distinction in the missions and roles of each organization enhances cooperations in tackling civil petition. Secondly the integration of civil petition process reduces time and improves efficiency. And lastly, the improvement of supplementary tools for the public is expected to minimize civil petitions. Future research needs to be conducted under the supervision of the Ministry of National Defense(MND). Factors such as systematic infrastructure for flight photography approval, related unit's reorganization following the defense reform 2.0, and guaranteed conditions for field security action units need to be ameliorated.

• Journal of the Korean Institute of Intelligent Systems
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• v.9 no.4
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• pp.384-388
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• 1999

This paper describes an approach for synthesizing a modularized gain scheduled PD type fuzzy logic controller(FLC) of nonlinear magnetic bearing system where the gains of FLC are on-line adapted according to the operating point. Specifically the systematic procedure via root locus technique is carried out for the selection of the gains of FLC. Simulation results demonstrate that the proposed gain scheduled fuzzy logic controller yields not only maximization of stability boundary but also better control performance than a single operating point (without gain scheduling)fuzzy controller.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.141.1-141
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• 2001

This paper describes an approach for synthesizing a modularized gain scheduled PD type fuzzy logic controller(FLC) for a high maneuverable aircraft system, where the gains of FLC are on-line adapted according to the flight condition. Specially, the systematic procedure via root locus technique is carried out for the sellection of the gains of FLC. Simulation results demonstrate that the proposed gain scheduled fuzzy logic controller yields better control performance than the normal (without gain scheduling) fuzzy controller.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1651-1654
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• 1997

Restiction of vertical and lateral accelerations is one of the very important requierments which has to be satisfied on the practice of automatically controlled flights of the civil aviation passenger planes. This goal could be achived on the basis of the optimization procedure using specilly constructed quadratic performance index. In the report the application of this procedure to the parameteric optimization of the control laws with known structure for autopilot of midium-size aircraft in the level flight model is demonstrated. Performance index is calculted on the basis of the controllability grammian. Results of simulation of control processes in the lateral and longitudinal channels sre represented.

• Aerospace Engineering and Technology
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• v.2 no.2
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• pp.58-65
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• 2003

KARI Electrical Test Team performed the SOH (State Of Health) test and Thermal Cycling test for small satellite of KOMPSAT-1 PFM at KARI SITC Highbay as per Storage plan every year, and verified that the system/subsystem units function installed on PFM were good without significant degradation causing from long-term storage. This paper describes the test items, test method, test procedure and selected test result data.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.13 no.4
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• pp.43-57
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• 2005

Traditionally aircraft had descended in steps to level at the MDA(Minimum Descent Altitude) during the conduct of non-precision approach. This "de-stabilized" method of flying an instrument approach procedure is considered as a major contributing factor in CFIT(Controlled Flight Into Terrain) accident and increasing pilot workload. In the effort to reduce CFIT accident and pilot workload, VNAV(Vertical Navigation) Approach has been suggested as means to manage the vertical component of non-precision approach procedure.[1] But In the actual circumstances in Korea, VNAV has not been using to reduce them because of many restriction facts and no published VNAV chart in particular airport. Therefore we are suggesting Constant Vertical Speed Approach Method, which is required few restriction facts, and the pilots who are using this method will experience a similar method like a Glideslope during proceeding non-precision approach. Consequently, We are expecting to reduce CFIT accidents and pilot workload.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.27 no.2
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• pp.70-78
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• 2019

CPDLC-DCL (Controller Pilot Data Link Communications-Departure Clearance) began in 2016 with 62 Towers in the United States. The application of this procedure is to utilize equipment different from existing ACARS PDCs or ACARS-DCLs. The purpose of this study is to provide information and understanding of CPDLC-DCL operation methods. Also, B747-8 aircraft considered operational cases related to departure procedures at U.S. airports. This procedure is currently not mandatory but will be mandatory in the future. The Flight Crew Procedures for CPDLC-DCL, as an appendix, will be a useful resource for B747-8 pilots.

• Advances in aircraft and spacecraft science
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• v.7 no.5
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• pp.441-458
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• 2020

Rectangular-to-Ellipse Shape Transition (REST) inlets are a class of inward turning inlets designed for hypersonic flight. The aerodynamic design of REST inlets involves very complex flows and shock-wave patterns. These inlets are used in highly integrated propulsive systems. Often the design of these inlets may require many geometrical constraints at different cross-section. In present work a design approach for hypersonic inward-turning inlets, adapted for REST inlets, is coupled with a multi-objective optimization procedure. The automated procedure iterates on the parametric representation and on the numerical solution of a base flow from which the REST inlet is generated by using streamline tracing and shape transition algorithms. The typical design problem of optimizing the total pressure recovery and mass flow capture of the inlet is solved by the proposed procedure. The accuracy of the optimal solutions found is discussed and the performances of the designed REST inlets are investigated by means of fully 3-D Euler and 3-D RANS analyses.