• Journal of the Korean Society for Aviation and Aeronautics
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• v.17 no.4
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• pp.94-106
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• 2009

오늘날 항공기사고는 우리나라뿐만 아니라 세계도처에서 때때로 발생되고 있다. 특히 항공기에 대한 갑작스러운 테로 공격 또는 일반 항공사고에 기인된 항공기의 추락 및 물건의 낙하로 인하여 지상에 있는 제3자에게 손해를 입히는 경우가 간혹 발생되고 있다. 이와 같은 항공사건에 있어 가해자(항공기 운항자)는 피해자(지상 제3자 등)에 대하여 불법행위책임을 부담하게 되는데 이러한 사건들을 해결하기 위하여 1952년의 개정로마조약과 1978년의 몬트리올의정서 등이 있음으로 본 논문에서는 이들 조약의 성립경위 및 주요내용과 개정이유 등을 간략하게 설명하였다. 특히 2001년 9월 11일에 뉴욕에서 발생된 이른바 항공기 납치에 의한 동시다발 테러 사건의 피해는 4대의 항공기에 탑승한 승객 및 승무원 266명이 전원 사망하였고 워싱턴에 있는 미국 방성청사에서의 사망 및 실종이 125명, 세계무역센터에서의 사망 및 실종이 약5,000여명에 달하는 막대한 피해가 발생되었다. 9/11참사사건은 지상에 있는 제3자의 인적 및 물적 손해가 거액에 달하였음으로 이에 따라 영국의 로이드보험 등 세계보험업계가 크게 손실을 입게 되어 항공보험을 기피하는 현상이 생겨나 법적인 문제점이 제기되었다. 국제민간항공기구(ICAO)에서는 9/11사태 이후 이와 같은 테로 사건의 법적대응책과 자구책을 마련하기 위하여 약 8년간의 심의 끝에 항공기에 대한 테로 공격(불법방해 행위)과 1952년 개정로마조약의 현대화(일반위험) 등 새로운 2개 조약을 2009년 5월 2일에 성립시켜 공표하였다. 상기 새로운 2개의 조약 중 첫째 조약은 항공기의 불법방해 행위에 기인된 제3자에 대한 손해 배상에 관한 조약(Convention on Compensation for Damage to Third Parties, Resulting from Acts of Unlawful Interference Involving Aircraft: 일명 불법방해조약이라고 호칭함: Unlawful Interference Convention)이고 둘째 조약은 항공기에 기인된 제3자에 대한 손해배상에 관한조약 (Convention on Compensation for Damage Caused by Aircraft to Third Parties: 일명 일반위험 조약이라고 호칭함: General Risk Convention) 이다. 본 논문에서는 이 새로운 2개 조약에 대한 ICAO가 주관한 성립경위와 주요 내용 및 필자의 논평을 제시하였고 이들 조약에 대하여 한국의 조속한 비준을 촉구하는 바이다.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.6
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• pp.46-52
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• 2016

Quasi-Orthogonal STBC (QO-STBC) scheme is proposed conventionally achieving approximate full rate and full diversity in more than 3 transmit antenna and open-loop environmen.. But, conventional QO-STBC has disadvantage that performance degradation by interference terms of detection matrix and high decoding complexity. Recently, this interference cancellation scheme of low decoding complexity by multiplying specific rotation matrix is proposed. We propose more general interference cancellation scheme by using EVD(Eigenvalue Decompostion).

• Journal of Aerospace System Engineering
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• v.4 no.2
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• pp.26-31
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• 2010

Reduction of the aerodynamic drag is one of the most hot issues of car industries. Many researchers have studied in the area of drag reduction methodology using experimental tools or numerical tools. In general, car shape design is the main focus to reduce the drag in aerodynamic research area. However, not many people have studied the aerodynamic interference between running cars to figure out the drag variation. In this research, the aerodynamic interference between two running cars have been analyzed by using numerical tools, FLUENT 6.2. Several different models of cars and two different distances between two running cars are considered.

• Korean Journal of Computational Design and Engineering
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• v.4 no.2
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• pp.110-120
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• 1999

In general, turbine blades are usually machined on 5-axis NC machine. The 5-axis machining of sculptured surface offers many advantages over 3-axis machining including the faster material-removal rates and an improved surface finish. But it is difficult and time-consuming to generated interference-free 5-axis tool path. This paper describes research on the algorithm for generation of an interference-free 5-axis NC data for machining turbine blades. The approach, using the section profile derived from the intersection of cutting planes with a triangulated-surface approximation, includes (1) CL-data generation by detecting an interference-free heel angle (2) the calculation method for finding a adaptive feed-rate value, and (3) the inverse kinematics depending on the structure of 5-axis machine.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.35-36
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• 2017

The finish works of construction projects comprises approximately 40% of the total construction duration. Thus, the management of finish works have as big as impacts on total project duration as the earthworks, foundation and structure works. Process interference management is considered one of the most important issues dealt during finish works. However, it was investigated that effective management systems have yet not been applied for practical use. Accordingly, this paper suggests a mobile technology based finish works management system that mainly focuses on preventing process interference occurred due to ineffective communication between general and sub-contractors.

• Journal of Aerospace System Engineering
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• v.3 no.3
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• pp.7-12
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• 2009

Reduction of the aerodynamic drag is one of the most hot issues of car industries. Many researchers have studied in the area of drag reduction methodology using experimental tools or numerical tools. In general, car shape design is the main focus to reduce the drag in aerodynamic research area. However, not many people have studied the aerodynamic interference between running cars to figure out the drag variation. In this research, the aerodynamic interference between two running cars have been analyzed by using numerical tools, FLUENT 6.2. Several different models of cars and two different distances between two running cars are considered.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.2
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• pp.127-134
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• 2017

Vortex Induced Vibration (VIV) is a typical flow-structure interference phenomenon which causes an unsteady flow pattern due to vortex shedding at or near the structure's natural frequency leading to resonant vibrations. VIV may cause premature fatigue failure of marine risers and pipelines. A test model was carried out to investigate the role of a stationary fairing by varying the caudal horn angle to suppress riser VIV taking into account the effect of wake interference. The test results show significant reduction of VIV for risers disposed in tandem and side-by-side. In general, fairing with a caudal horn of $45^{\circ}$ and $60^{\circ}$ are efficient in quelling VIV in risers. The results also reveal fairing can reduce the drag load of risers arranged side-by-side. For the tandem configuration, a fairing can reduce the drag load of an upstream riser, but will enlarge the drag force of the downstream riser.

• Journal of Auto-vehicle Safety Association
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• v.8 no.2
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• pp.30-36
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• 2016

According to revolutionary developments in automobile technologies, various electronically controlled components of vehicles are rapidly increasing. A variety of advanced vehicles (hybrid vehicle, hydrogen fuel-cell vehicle, electric vehicle, etc.) using electrical energy source are increasing, too. The electromagnetic compatibility is getting more important for development of a vehicle because those advanced vehicles are equipped with more new electronic systems. In general, electromagnetic compatibility tests consist of an electromagnetic interference (EMI) test and an electromagnetic susceptibility (EMS) test. In this paper, in order to investigate the electromagnetic interference in the cabin of vehicle by various electric and electronic components of vehicles, a series of narrowband electromagnetic emission tests are conducted. For comparison, the several digital home appliances (smartphone under charging, laptop compuer and digital camera), which are used a lot in daily lives, are tested.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.5
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• pp.39-43
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• 2020

In this paper, we propose the multi-channel interference cancellation algorithm for visible light communication (VLC) in smart building. The VLC system is communication technology using visible rays that come out in Light Emitting Diode (LED) device. It has energy curtailment effect and possible to use in ubiquitous network service applications. When a large number of users communicate indoors, the performance can be reduced due to channel interference. To remove interference, at the first, the minimum mean square error (MMSE) scheme as interference cancellation methods used, and then the successive interference cancellation (SIC) is applied to obtain additional diversity gain and improve interference cancellation performance. Indoor VLC channel model is employed. The performance is evaluated in terms of bit error rate (BER). From the simulation results, it is confirmed that the proposed scheme has better BER performance compared to the previous systems. As a result, the proposed interference cancellation improves the signal quality of VLC systems by effectively removing the channel noise. The results of the paper can be applied to VLC for smart building and general communication systems.

• KNOM Review
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• v.23 no.1
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• pp.43-50
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• 2020

As General Purpose Graphics Processing Unit (GPGPU) recently plays an essential role in high-performance computing, several cloud service providers offer GPU service. Most cluster orchestration platforms in a cloud environment using containers allocate the integer number of GPU to jobs and do not allow a node shared with other jobs. In this case, resource utilization of a GPU node might be low if a job does not intensively require either many cores or large size of memory in GPU. GPU virtualization brings opportunities to realize kernel concurrency and share resources. However, performance may vary depending on characteristics of applications running concurrently and interference among them due to resource contention on a node. This paper proposes GPU container co-execution framework with multiple server creation and execution based on Kubernetes, container orchestration platform for measuring interference which may be occurred by sharing GPU resources. Performance changes according to scheduling policies were investigated by executing several jobs on GPU. The result shows that optimal scheduling is not possible only considering GPU memory and computing resource usage. Interference caused by co-execution among applications is measured using the framework.