• 한국항공우주학회지
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• 제48권2호
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• pp.159-166
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• 2020

본 연구는 복잡한 다수 무인기 시스템을 효율적으로 운용하기 위해 이산 사건 모델 기반의 다수 무인기 이종 임무 할당 기법을 제안한다. 이종 임무의 생성, 임무 할당, 무인기 출동, 임무 수행, 무인기 수리 및 정비에 이르는 무인기의 임무 시작에서 종료까지 일련의 과정을 이산 사건 모델링을 통해 수학적으로 정의하고, 이를 기반으로 주어진 임무 상황에서 필요한 최적 무인기 대수를 도출한다. 도출된 최적 무인기 대수를 적용하여 이산 사건 모델 기반의 반복 시뮬레이션을 통해 그 결과를 검증한다. 제안된 이종 임무 할당 기법으로 운용자는 제한된 무인기 자원을 효율적으로 활용하여 주어진 임무 상황에서 최적의 임무 계획을 수립할 수 있다.

• 해양환경안전학회지
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• 제9권1호
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• pp.65-72
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• 2003

최근 해양사고를 예방하기 위해 다양한 정책과 대응방안이 개발되고 있다. 연안해역에 항행안전성을 증가시키기 위해서 항행안전성은 조선자의 관점에서 평가되어야 한다. 항행 안전성 평가와 같은 문제에 있어 인간의 사고에는 많은 형태의 애매함이 존재한다. 이러한 평가에서 애매함을 반영하기 위해 본 연구에서는 퍼지척도와 쇼케적분을 소개하였다. 본 연구의 목적은 퍼지척도와 쇼케적분을 이용하여 조선부담감의 관점에서 평가모델을 개발하였다. 그리고 본 연구에서는 우리나라 연안해역을 8개로 나누고 연안 VTS와 항행보조시설 설치의 우선순위를 결정하기 위한 평가를 실시하였다. 그 결과 목포, 여수, 포항, 인천, 부산, 거제, 군산, 동해근해 해역순으로 안전성이 낮게 평가되었다.

• 한국시뮬레이션학회논문지
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• 제23권4호
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• pp.75-83
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• 2014

함정 전투체계는 각종 센서 및 무장을 포함한 플랫폼들을 효율적으로 통제하기 위해서 운용자의 개입을 필요로 한다. 이러한 문제점을 극복하기 위해서 다중 에이전트 기반의 M&S(Modeling and Simulation) 기술이 도입되어 다양한 연구가 이루어져 왔다. 하지만 다중 플랫폼간의 높은 임무 복잡도를 필요로 하는 대 잠수함 전투에 있어서는 M&S 시스템을 통한 전술에 관한 연구가 거의 진행되지 않은 실정이다. 본 연구에서는 다중 에이전트 기반의 M&S 기술을 대 잠수함 전투에 적용하였다. 이를 위해 함정, 잠수함, 헬기 등 다수의 플랫폼을 에이전트 기반으로 모델링함으로써 HVU(High Value Unit) 호위 임무를 위한 모델 구조를 제시하였다. 이를 통해 다양한 전장상황에 대한 다양한 전술 효과도를 분석할 수 있었다. 그 결과 조건별 최적의 전술적 효과를 확인할 수 있었다. 국방 관계자들이 본 연구에서 제안한 방법론을 도입하여 상세한 모델 변수값들을 대입한다면 보다 실질적인 대 잠수함 전술 효과도를 분석해 낼 수 있을 것으로 기대된다.

• Journal of Biosystems Engineering
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• 제39권1호
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• pp.21-33
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• 2014

Background: Significant technological development and changes happened in the tractor industries. Contrariwise, the test procedures of the major standard development organizations (SDO's) remained unchanged or with a little modification over the years, demanding new tractor test standards or improvement of existing ones for tractor performance, safety, and comfort. Purpose: This study focuses on reviewing the research trends regarding performance, safety and comfort evaluation of agricultural tractors. Based on this review, few recommendations were proposed to revise or improve the current test standards. Review: Tractor power take-off power test using the DC electric dynamometer reduced human error in the testing process and increased the accuracy of the test results. GPS signals were used to determine acceleration and converted into torque. High capacity double extended octagonal ring dynamometer has been designed to measure drawbar forces. Numerical optimization methodology has been used to design three-point hitch. Numerous technologies, driving strategies, and transmission characteristics are being considered for reducing emissions of gaseous and particulate pollutants. Engine emission control technology standards need to be revised to meet the exhaust regulations for agricultural tractors. Finite Element Analysis (FEA) program has been used to design Roll-Over Protective Structures (ROPS). Program and methodology has been presented for testing tractor brake systems. Whole-body vibration emission levels have been found to be very dependent upon the nature of field operation performed, and the test track techniques required development/adaptation to improve their suitability during standardized assessment. Emphasizes should be given to improve visibility and thermal environment inside the cab for tractor operator. Tractors need to be evaluated under electromagnetic compatibility test conditions due to large growing of electronic devices. Research trends reviewed in this paper can be considered for possible revision or improvement of tractor performance, safety, and comfort test standards.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.62-67
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• 2004

Many ships in voyage experience weight and buoyancy distribution change by various reasons such as change of sea water density and waves, weather condition, and consumption of fuel, provisions, etc . The weight and buoyancy distribution change can bring the ships out of allowable trim, heeling angle. In these case, the ships should adjust trim and heeling angle by shifting of liquid cargo or ballasting, deballasting of ballast tanks for recovery of initial state or for a stable voyage. But, if the adjustment is performed incorrectly, ship's safety such as longitudinal strength, intact stability, propeller immersion, wide visibility, minimum forward draft cannot be secured correctly. So it is required that the adjustment of trim and heeling angle should be planned not by human operators but by optimization computer algorithm. To make an optimized plan to adjust trim and heeling angle guaranteeing the ship's safety and quickness of process, Uk! combined mechanical analysis and optimization algorithm. The candidate algorithms for the study were heuristic algorithm, meta-heuristic algorithm and uninformed searching algorithm. These are widely used in various kinds of optimization problems. Among them, heuristic algorithm $A^\ast$ was chosen for its optimality. The $A^\ast$ algorithm is then applied for the study. Three core elements of $A^\ast$ Algorithm consists of node, operator, evaluation function were modified and redefined. And we analyzed the $A^\ast$ algorithm by considering cooperation with loading instrument installed in most ships. Finally, the algorithm has been applied to tanker ship's various conditions such as Normal Ballast Condition, Homo Design Condition, Alternate Loading Condition, Also the test results are compared and discussed to confirm the efficiency and the usefulness of the methodology developed the system.

• Genomics & Informatics
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• 제13권3호
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• pp.70-75
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• 2015

MicroRNAs (miRNAs) have been demonstrated to play an important role in carcinogenesis. Previous studies revealed that miRNAs are present in human plasma in a remarkably stable form that is protected from endogenous RNase activity. In this study, we measured the plasma expression levels of three miRNAs (miR-21, miR-27a, and miR-155) to investigate the usefulness of miRNAs for gastric cancer detection. We initially examined plasma miRNA expression levels in a screening cohort consisting of 15 patients with gastric cancer and 15 healthy controls from Korean population, using TaqMan quantitative real-time polymerase chain reaction. We observed that the expression level of miR-27a was significantly higher in patients with gastric cancer than in healthy controls, whereas the miR-21 and miR-155a expression levels were not significantly higher in the patients with gastric cancer. Therefore, we further validated the miR-27a expression level in 73 paired gastric cancer tissues and in a validation plasma cohort from 35 patients with gastric cancer and 35 healthy controls. In both the gastric cancer tissues and the validation plasma cohort, the miR-27a expression levels were significantly higher in patients with gastric cancer. Receiver-operator characteristic (ROC) analysis of the validation cohort, revealed an area under the ROC curve value of 0.70 with 75% sensitivity and 56% specificity in discriminating gastric cancer. Thus, the miR-27a expression level in plasma could be a useful biomarker for the diagnosis and/or prognosis of gastric cancer.

• 한국화재소방학회논문지
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• 제34권3호
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• pp.116-125
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• 2020

본 연구는 재난현장 소방공무원 회복실 설치에 대한 근거를 제공하여 소방공무원의 안전과 회복탄력을 위한 회복실 설치 모델을 제공하고자 한다. 연구목적을 달성하기 위하여, 우리는 소방공무원을 대상으로 회복실의 효과성 검증을 위한 설문조사 및 빈도분석과 분산분석을 실시하였다. 연구의 결과를 바탕으로 효과적인 회복실을 운영하기 위한 정책적 제언은 다음과 같다. 각 소방본부에 회복실 운영을 위한 조직이 구축되어야 하고, 회복실 운영을 위한 인적자원을 확보하여야 한다. 그리고 회복실 운영책임자의 임무 내용, 회복실 운영자의 임무 내용, 회복실 운영절차 등 세부적인 운영기준이 마련되어야 하고, 회복과 회복실에 대한 이해를 높일 수 있는 교육이 필요하다.

• 한국IT서비스학회지
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• 제15권4호
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• pp.25-39
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• 2016

The drone is an unmanned aerial vehicle which has no human pilot. Drones can be classified into military drones, commercial drones, and personal drones by usage. Also, drones can be classified from large-sized to nano-sized drone by size and autonomous, remote controlled drone by control type. Especially, military drones can be classified into low-altitude drones, medium-altitude, and high-altitude drones by altitude. Recently, the drone industry is one of the fast growing industries in the world. As drone technologies have become more advanced and cost-effective, Korean government has set its goal to become a top-level country in drone business. However, the government's strict regulation for drone operations is one of the biggest hurdles for the development of the related technologies in Korea and other countries. For example, critical problems for drone delivery can be classified into technical issues and institutional issues. Technical issues include durability, conditional awareness, grasp and release mechanisms, collision avoidance systems, drone operating system. Institutional issues include pilot and operator licensing, privacy rules, noise guidelines, security rules, education for drone police. This study analyzes the trends of the drone industry from the viewpoint of technology and regulation. Also, we define the business areas of drone utilization. Especially, the drone business types or models for public sector are proposed. Drone services or functions promoting public interests need to be aligned with the business reference model of Korean government. To define ten types of drone uses for public sector, we combine the business types of government with the future uses of drones that are proposed by futurists and business analysts. Future uses of drones can be divided into three sectors or services. First, drone services for public or military sectors include early warning systems, emergency services, news reporting, police drones, library drones, healthcare drones, travel drones. Second, drone services for commercial or industrial services include parcel delivery drones, gaming drones, sporting drones, farming and agriculture drones, ranching drones, robotic arm drones. Third, drone services for household sector include smart home drones.

• Journal of Information Processing Systems
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• 제10권1호
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• pp.1-22
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• 2014

Recent technological advances provide the opportunity to use large amounts of multimedia data from a multitude of sensors with different modalities (e.g., video, text) for the detection and characterization of criminal activity. Their integration can compensate for sensor and modality deficiencies by using data from other available sensors and modalities. However, building such an integrated system at the scale of neighborhood and cities is challenging due to the large amount of data to be considered and the need to ensure a short response time to potential criminal activity. In this paper, we present a system that enables multi-modal data collection at scale and automates the detection of events of interest for the surveillance and reconnaissance of criminal activity. The proposed system showcases novel analytical tools that fuse multimedia data streams to automatically detect and identify specific criminal events and activities. More specifically, the system detects and analyzes series of incidents (an incident is an occurrence or artifact relevant to a criminal activity extracted from a single media stream) in the spatiotemporal domain to extract events (actual instances of criminal events) while cross-referencing multimodal media streams and incidents in time and space to provide a comprehensive view to a human operator while avoiding information overload. We present several case studies that demonstrate how the proposed system can provide law enforcement personnel with forensic and real time tools to identify and track potential criminal activity.

• 한국시뮬레이션학회논문지
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• 제28권1호
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• pp.93-98
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• 2019

현대에서 사용되는 무인 비행체의 경우 자율화수준이 떨어져 사용자의 개입이 필요하다는 문제가 있다. 이에 본 연구는 자율화 달성의 방법론으로 유전자 알고리즘을 선택하고, 이것을 적용해 무인 착륙체의 자율화 가능성을 확인해 보는 것이다. 특별히 무인 비행체의 착륙은 비행체에서 매우 중요한 고전적인 과업 중의 하나이며, 착륙에 있어서 역사적 사건 중의 하나가 달착륙이라고 할 수 있다. 달 착륙선의 추동 메카니즘을 장착한 낙하체의 착륙 자율화 방법을 이용해 무인 착륙체의 자율화 가능성을 확인한다. 본 논문에서는 유전자알고리즘 적용시 게놈을 단지 4가지 액션 (좌회전, 우회전, 분출, 자유낙하) 으로 인코딩하여 무인 착륙체에 적용하고, 유전자 알고리즘의 주요 연산을 접목하여 실험을 성공적으로 진행하였으며 센서에 대한 의존도를 최소화할 수 있는 무인 비행체의 모의 UAV를 제작하였고, 유전자알고리즘을 적용해 그 가능성을 확인하는 테스트 베드를 구축하였다.