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A Review of Routing Plan for Unmanned Aerial Vehicle : Focused on In-Country Researches (국내 무인항공기의 경로계획 연구)

  • Kim, Jinwoo;Kim, Jinwook;Chae, Junjae
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.38 no.4
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    • pp.212-225
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    • 2015
  • UAV (Unmanned Aerial Vehicle), the pilotless plane or drone, draws researchers' attention at these days for its extended use to various area. The research was initiated for military use of the UAV, but the area of applicable field is extended to surveillance, communication, and even delivery for commercial use. As increasing the interest in UAV, the needs of research for operating the flying object which is not directly visible when it conducts a certain mission to remote place is obviously grown as much as developing high performance pilotless plane is required. One of the project supported by government is related to the use of UAV for logistics fields and controlling UAV to deliver the certain items to isolated or not-easy-to-access place is one of the important issues. At the initial stage of the project, the previous researches for controlling UAV need to be organized to understand current state of art in local researches. Thus, this study is one of the steps to develop the unmanned system for using in military or commercial. Specifically, we focused on reviewing the approaches of controlling UAV from origination to destination in previous in-country researches because the delivery involves the routing planning and the efficient and effective routing plan is critical to success to delivery mission using UAV. This routing plan includes the method to avoid the obstacles and reach the final destination without a crash. This research also present the classification and categorization of the papers and it could guide the researchers, who conduct researches and explore in comparable fields, to catch the current address of the research.

Structural Analysis for Newly Installed Blade Antenna of Rotorcraft (신규 블레이드 안테나 장착을 위한 노후 회전익 항공기 구조 해석 연구)

  • Yu, Jeong-O;Kim, Jae-Yong;Choi, Hang-Suk
    • Journal of Aerospace System Engineering
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    • v.15 no.5
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    • pp.106-112
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    • 2021
  • In this study, we performed a design and structural analysis of a blade-shaped antenna installation on the rear fuselage of a rotary wing aircraft operated by the military. When the structure is damaged while the aircraft is in operation, it is separated from the aircraft main structure and may collide with the rotor or blades to cause the aircraft to crash. Therefore, structural safety for the modified structure must be secured. The design requirement for the newly installed modified part were established, and the load condition was constructed by applying the load that may occur in the aircraft after the modification. Structure safety for the modified structure was secured by performing structure analysis. To analysis stress and deformation of aircraft structure, we developed finite element model and verified it by using hand calculation method. We confirmed the safety of the modified structure through the final structural integrity analysis.

Analysis of Tendency and Characteristics in Armed Conflict in Post-Cold War Era: on the basis of UCDP (탈냉전 후 무력갈등의 추세와 특징에 관한 분석: UCDP 자료를 중심으로)

  • LEE, CHULKI
    • International Area Studies Review
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    • v.18 no.3
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    • pp.269-291
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    • 2014
  • The purpose of this article is to analyze the tendency and characteristics in armed conflict in post-Cold War era on the basis of Uppsala conflict data program(UCDP) datasets. The collapse of bipolarity and the end of cold War proved a watershed in the dynamics of international conflict. The major shift in the nature of conflict has been away from interstate conflict, leaving intrastate conflict. Major powers have acted carefully against each other and been willing to understand the interests of other to avoid military confrontation and crash. As the means of termination for armed conflict, there is a stronger emphasis on the peace settlement like peace agreement and ceasefire agreement than military victory. Many intrastate conflicts become internationalized, through the involvement of diaspora communities, or regionalized through a spillover effect into neighboring countries. Since the end of the Cold War, the UN has taken a much more active role in conflict management and conflict resolution.

Development of Safety Evaluation Scenarios for Autonomous Vehicle Tests Using 5-Layer Format(Case of the Community Road) (5-레이어 포맷을 이용한 자율주행자동차 실험 시나리오 개발(커뮤니티부 도로를 중심으로))

  • Park, Sangmin;So, Jaehyun(Jason);Ko, Hangeom;Jeong, Harim;Yun, Ilsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.2
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    • pp.114-128
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    • 2019
  • Recently, the interest in the safety of autonomous vehicles has globally been increasing. Also, there is controversy over the reliability and safety about autonomous vehicle. In Korea, the K-City which is a test-bed for testing autonomous vehicles has been constructing. There is a need for test scenarios for autonomous vehicle test in terms of safety. The purpose of this study is to develop the evaluation scenario for autonomous vehicle at community roads in K-City by using crash data collected by the Korea National Police Agency and a text-mining technique. As a result, 24 scenarios were developed in order to test autonomous vehicle in community roads. Finally, the logical and concrete scenario forms were derived based on the Pegasus 5-layer format.

Convolutional neural network based traffic sound classification robust to environmental noise (합성곱 신경망 기반 환경잡음에 강인한 교통 소음 분류 모델)

  • Lee, Jaejun;Kim, Wansoo;Lee, Kyogu
    • The Journal of the Acoustical Society of Korea
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    • v.37 no.6
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    • pp.469-474
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    • 2018
  • As urban population increases, research on urban environmental noise is getting more attention. In this study, we classify the abnormal noise occurring in traffic situation by using a deep learning algorithm which shows high performance in recent environmental noise classification studies. Specifically, we classify the four classes of tire skidding sounds, car crash sounds, car horn sounds, and normal sounds using convolutional neural networks. In addition, we add three environmental noises, including rain, wind and crowd noises, to our training data so that the classification model is more robust in real traffic situation with environmental noises. Experimental results show that the proposed traffic sound classification model achieves better performance than the existing algorithms, particularly under harsh conditions with environmental noises.

The Comparison and Analysis of Maritime Precise Positioning using GPS Based Smartphone

  • Park, Sul Gee;Park, Sang Hyun
    • Journal of Positioning, Navigation, and Timing
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    • v.7 no.4
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    • pp.217-226
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    • 2018
  • According to the Korea Coast Guard's maritime disaster statistics (Korea Coast Guard 2017, Korean Statistical information Service 2018), an average of 2,140 marine accidents occurred every year for the past 6 years and the number of accidents is increasing every year. Among them, maritime accidents of fishing vessels are the most frequent, and recently accidents involving fishing boat and leisure vessels are rapidly increasing as well. In particular, the number of accidents involving leisure vessels increased to about one-third of the accidents of fishing vessels, and emergency rescue requests are increasing every year accordingly. However, the number of crash accidents involving users of small vessels and marine leisure activities are increasing because of the difficulties of installing navigation equipment and electronic navigation charts. Recently, the demand for precise positioning using mobile devices is increasing in the fields of maritime safety, piloting support, and coastal survey. Although various applications of smart devices provide location-based services for users, the measurement results are discontinuous when using the position coordinates of the National Marine Electronics Association (NMEA) calculated by smartphone. Recently, Google announced that they will provide GPS raw data to developers from Android 7.0 Nougat. As a result, developers have an opportunity to receive precise carrier phase and code measurements to make more accurate positioning according to the performance of Android devices. This study analyzed GPS positioning performance using Android devices, and compared and analyzed the positioning performance at sea with high-performance GPS receivers.

Single-Center Retrospective Study on the Status of Korean Medicine Automobile Insurance Treatment and Usage of Main Pharmacopuncture (단일 한의원 교통사고 환자 258례에 대한 한방치료 효과 후향적 연구)

  • Hwang, Ji Hye;Jung, Chul
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.33 no.3
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    • pp.181-190
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    • 2019
  • In South Korea, traffic accident patients can be treated under automobile insurance coverage. This study investigated the status of Korean medicine (KM) Automobile insurance system and usage status of main pharmacopuncture in KM clinic which reported that the largest number of automobile insurance fee claims among medical institutions. We surveyed 258 traffic accident patients who were treated at Namsangcheon KM clinic from 2014 to 2018 according to medical chart. The majority of the patients were male and thirties. In traffic accident situation, the highest distribution was car to car crash with 85.66% and 66.67% of the patients visited in the most acute phase. The most frequent treatment period was within 4 weeks and the number of treatments was 10 or less with 72.87%. In total results of treatment, the distribution was exellent with 10.08%, good with 46.90%, fair with 27.13% and poor with 15.89%, and the effective rate was 84.11%. The most frequent treatment period was within 4 weeks with 64.73% and the number of treatments was 10 or less with 72.87%. Of the 242 patients who received pharmacopunture, 91.5% were treated with HO, which was named after Honghwaja and TA, which was named after traffic accidents, and there were significant differences in the number of treatments and symptom improvement between the two groups. In this study, we confirmed the status of automobile insurance treatment and usage of main pharmacopuncture of single KM clinic with symptom improvement. This study can be regarded as one of the basis of KM treatment for the rapidly growing automobile insurance market.

A DOM-Based Fuzzing Method for Analyzing Seogwang Document Processing System in North Korea (북한 서광문서처리체계 분석을 위한 Document Object Model(DOM) 기반 퍼징 기법)

  • Park, Chanju;Kang, Dongsu
    • KIPS Transactions on Computer and Communication Systems
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    • v.8 no.5
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    • pp.119-126
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    • 2019
  • Typical software developed and used by North Korea is Red Star and internal application software. However, most of the existing research on the North Korean software is the software installation method and general execution screen analysis. One of the ways to identify software vulnerabilities is file fuzzing, which is a typical method for identifying security vulnerabilities. In this paper, we use file fuzzing to analyze the security vulnerability of the software used in North Korea's Seogwang Document Processing System. At this time, we propose the analysis of open document text (ODT) file produced by Seogwang Document Processing System, extraction of node based on Document Object Mode (DOM) to determine test target, and generation of mutation file through insertion and substitution, this increases the number of crash detections at the same testing time.

Analysis for Traffic Accident of the Bus with Advanced Driver Assistance System (ADAS) (첨단안전장치 장착 버스의 사고사례 분석)

  • Park, Jongjin;Choi, Youngsoo;Park, Jeongman
    • Journal of Auto-vehicle Safety Association
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    • v.13 no.3
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    • pp.78-85
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    • 2021
  • Recently a traffic accident of heavy duty vehicles under the mandatory installation of ADAS (Advanced Driver Assistance System) is often reported in the media. Heavy duty vehicle accidents are normally occurring a high number of passenger's injury. According to report of Insurance Institute for Highway Safety, FCW (Forward Collision Warning) and AEB (Automatic Emergency Braking) were associated with a statistically significant 12% reduction in the rate of police-reportable crashes per vehicle miles traveled, and a significant 41% reduction in the rear-end crash rate of large trucks. Also many countries around the world, including Korea, are studying the effects of ADAS installation on accident reduction. Traffic accident statistics of passenger vehicle for business purpose in TMACS (Traffic safety information Management Complex System in Korea) tends to remarkably reduce the number of deaths due to the accident (2017(211), 2018(170), 2019(139)), but the number of traffic accidents (2017(8,939), 2018(9,181), 2019(10,095)) increases. In this paper, it is introduced a traffic accident case that could lead to high injury traffic accidents by being equipped with AEB in a bus. AEB reduces accidents and damage in general but malfunction of AEB could occur severe accident. Therefore, proper education is required to use AEB system, simply instead of focusing on developing and installing AEB to prevent traffic accidents. Traffic accident of AEB equipped vehicle may arise a new dispute between a driver's fault and vehicle defect. It is highly recommended to regulate an advanced event data recorder system.

Small UAV Failure Rate Analysis Based on Human Damage on the Ground Considering Flight Over Populated Area (도심 지역 비행을 위한 지상 인명 피해 기반 소형무인기 고장 빈도 분석)

  • Kim, Youn-Sil;Bae, Joong-Won
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.9
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    • pp.781-789
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    • 2021
  • In this paper, we quantitatively analyzed the required UAV(Unmanned Aerial Vehicle) failure rate of small UAV (≤25kg) based on the harm to human caused by UAV crash to fly over the populated area. We compute the number of harm to human when UAV falls to the ground at certain descent point by using population density, car traffic, building to land ratio, number of floors of building data of urban area and UAV descent trajectory modeling. Based on this, the maximum allowable UAV failure rate is calculated to satisfy the Target Level of Safety(TLS) for each UAV descent point. Then we can generate the failure rate requirement in the form of map. Finally, we divide UAV failure rate into few categories and analyze the possible flight area for each failure rate categories. Considering the Youngwol area, it is analyzed that the UAV failure rate of at least 10-4 (failure/flight hour) is required to access the residential area.