• 한국군사과학기술학회지
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• 제16권6호
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• pp.726-732
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• 2013

It is required for UGV(Unmanned Ground Vehicle) to have a LPP(Local Path Plan) component which generate a local path via the center of road by analyzing binary map to travel autonomously unpaved road in rough environment. In this paper, we present the method of boundary estimation for unpaved road and a local path planning method based on RANGER algorithm using the estimated boundary. In specially, the paper presents an approach to estimate road boundary and the selection method of candidate path to minimize the problem of zigzag driving based on Bayesian probability reasoning. Field test is conducted with scenarios in rough environment in which bush, tree and unpaved road are included and the performance of proposed method is validated.

• 대한임베디드공학회논문지
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• 제14권3호
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• pp.151-156
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• 2019

According to recent advances in technology, major robot technologies that have been developed and commercialized for industrial use are being applied to various fields in our everyday life such as guide robots and cleaning robots. Among them, the navigation based on the self localization has become an essential element technology of the robot. In the case of indoor environment, many high-priced sensors are used, which makes it difficult to activate the robot industry. In this paper, we propose a robotic platform and a moving algorithm that can travel by using Dijkstra algorithm. The proposed system can find a short route to the destination with its own position. Also, its performance is discussed through the experimentation of an actual robot.

• International Journal of Internet, Broadcasting and Communication
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• 제13권3호
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• pp.56-62
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• 2021

MSRDS(Microsoft Robotics Developer Studio) provides the ability to simulate these technologies. SPL(Simple Programming Language) of MSRDS provides many functions for sensor programming to control autonomous robots. Sensor programming in SPL can be implemented in two types of schemes: procedure sensor notification and while-loop schemes. We considered the three programming schemes to control the robot movement after studying the advantages and disadvantages of the sensor notification procedure and the while-loop scheme. We also created simulation environments to evaluate the performance of the three considered schemes when applied to four different mazes. The simulation environment consisted of a maze and a robot with the most powerful sensor, i.e., the LRF(Laser Range Finder) sensor. We measured the required travel time and robot actions (number of turns and number of collisions) needed to escape the maze and compared the performance outcomes of the three considered schemes in the four different mazes.

• 한국인터넷방송통신학회논문지
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• 제19권2호
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• pp.243-253
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• 2019

행성 탐사의 첫 번째 단계는 일반적으로 자율적 탐사선을 사용하여 수행된다. 이 탐사선은 자신의 길을 찾고 행성표면에 대한 실험을 수행 할 수 있다. 이 논문에서는 각 에이전트의 지식과 노력을 공유하기 위해 블랙보드 시스템을 효과적으로 활용하는 다중 에이전트 시스템을 제안한다. 에이전트는 BDI (Belief Desire Intension) 모델의 조합으로 반응 모델을 사용하고 최단 거리를 계산하고 행성 표면에서 이동 경로를 계산하는 경로 찾기 알고리즘을 사용한다. 이 접근법은 짧은 시간 내에 주어진 지형에서 표면 탐사를 수행 할 수 있다. 블랙보드에 수집 된 정보는 상세한 표면 토양 변화 결과를 산출하는데 사용된다. 이 연구에서 제안된 다중 에이전트 시스템에 의한 탐사는 다양한 지형 크기별로 잘 수행되는 것으로 나타났다.

• 한국발생생물학회지:발생과생식
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• 제14권1호
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• pp.27-34
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• 2010

A fertilized oocyte can get the competence for implantation through cleavage and stage-specific gene expression. These are under the control of autonomous and exogenous regulators including physiological culture condition. Endogenous and exogenous growth factors are considered as critical regulators of cleaving embryos during travel the oviduct and uterus. In this study, an effort was made to evaluate comprehensively the quality of embryos for implantation, grown in media enriched with EGF and PAF. The study evaluated developmental rates on given time, blastulation and hatching rates, and adhesion rates. Developmental rates of blastocyst to the hatching stage were significantly high in PAF treated group compared to the control in a dose-dependent manner but not in EGF group. Implantation rates were significantly high both PAF and EGF in a dose-dependent manner. H7, a PKC inhibitor, blocked the process of hatching of the blastocysts but combined treatment of EGF and PAF enhanced the hatching and implantation of blastocsyts. Based on these results it is suggested that EGF and PAF support acquirement of implantation competence at blastocyst stage through a PKC pathway.

• 한국환경교육학회지:환경교육
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• 제15권2호
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• pp.76-85
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• 2002

As exchanges and cooperations among Korea, Japan and China about environmental issues become active, exchange programs about social environmental education increases. Therefore, in this study, the present state of the social environmental educations in Korea, Japan and China is analyzed and compared. The conclusions are as following. First, the social environmental education in Korea is mainly executed by NGOs about environment, religion and gender. In the social environmental education in Korea, education for sensibility in which all the people can participate such as field investigation, camping and travel holds the majority. However, the education about social-political knowledge which deals with environmental policy and economy is not sufficient. Second, in the social environmental education in Japan, the education of environmental education methods and knowledge about environmental issues, in which citizens participate such as workshop and forum holds the majority. Third, the social environmental education in China is mainly executed by CEEC under SEPA. Education toward teenagers for fostering environment-friendly attitude is mostly active, and lectures are in general. However, education for the specific knowledge of environmental issues is not enough. The social environmental education is very significant as lifelong education for environment friendly welfare society since civil decision-making leads directly the social behavior. Therefore, efforts must be made to develop the social environmental education of each countries by means of active exchange and energetic support of the social environmental education program and autonomous exchange of NGOs for the social environmental education.

• Journal of electromagnetic engineering and science
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• 제11권4호
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• pp.298-303
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• 2011

A capsular endoscope (CE) for inspection of the large intestine requires a motor for backward navigation against the autonomous travel in the intestine. This study proposes an HF power system for generating a magnetic field and for delivering wireless power to the internal or implanted medical devices. The magnetic field is generated by a wound coil (L) around a wooden frame, and the current is driven to the coil through a resonating capacitor (C). The characteristics of the resonance frequency shifting of the L-C series circuit are analyzed. A stable magnetic field intensity in the field coil is maintained by a specially designed frequency tracking system that automatically follows the L-C resonance frequency. Testing confirmed that the oscillation system tracks well the parameter changes of the electric components caused by the operating conditions or environmental variations.

• 한국군사과학기술학회지
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• 제14권3호
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• pp.327-334
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• 2011

It is necessary that UGV(Unmanned Ground Vehicle) should generate a real-time travesability index map by analyzing raw terrain information to travel autonomously tough terrain which has various slope and roughness values. In this paper, we propose a local path planning method, $MA^*$(Modified $A^*$) algorithm, using DVGM (Directional Velocity Grid Map) for unmanned ground vehicle. We also present a path optimization algorithm and a path smoothing algorithm which regenerate a pre-planned local path by $MA^*$ algorithm into the reasonable local path considering the mobility of UGV. Field test is conducted with UGV in order to verify the performance of local path planning method using DVGM. The local path planned by $MA^*$ is compared with the result of $A^*$ to verify the safety and optimality of proposed algorithm.

• 한국ITS학회 논문지
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• 제11권4호
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• pp.10-18
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• 2012

본 논문은 최근 지능형교통시스템에서 중요한 수단으로 간주되고 있는 차량 간 통신을 이용한 분산식 첨단 교통정보시스템을 개발하고자 한다. 또한 독립자동유고감지 기능을 통해서 제안된 첨단 교통정보시스템의 효과를 개선하고자 한다. 이상적인 통신 환경을 가정한 단순화된 교통네트워크에서 미시적 시뮬레이션 모델인 VISSIM을 통해 제안된 첨단 교통정보시스템을 구현하였으며 특히 비반복적으로 일어나는 교통상황(예를 들면, 교통사고)을 사용하여 모델의 효과를 관찰하였다. 결론적으로 본 연구에서는 차량 간 통신을 통한 첨단 교통정보시스템의 효율성을 확인함과 동시에 독립자동 유고감지 기능이 시스템의 성능을 향상시키는 것을 보여주고 있다.

• 대한임베디드공학회논문지
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• 제19권2호
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• pp.91-99
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• 2024

Collision avoidance system is important to improve the robustness and functional safety of autonomous vehicles. This paper proposes an object-level distance estimation method to develop a collision avoidance system, and it is applied to golfcarts utilized in country club environments. To improve the detection accuracy, we continually trained an object detection model based on pseudo labels generated by a pre-trained detector. Moreover, we propose object-aware depth estimation (OADE) method which trains a depth model focusing on object regions. In the OADE algorithm, we generated dense depth information for object regions by utilizing detection results and sparse LiDAR points, and it is referred to as object-aware LiDAR projection (OALP). By using the OALP maps, a depth estimation model was trained by backpropagating more gradients of the loss on object regions. Experiments were conducted on our custom dataset, which was collected for the travel distance of 22 km on 54 holes in three country clubs under various weather conditions. The precision and recall rate were respectively improved from 70.5% and 49.1% to 95.3% and 92.1% after the continual learning with pseudo labels. Moreover, the OADE algorithm reduces the absolute relative error from 4.76% to 4.27% for estimating distances to obstacles.