• Title/Summary/Keyword: aerial photography

Search Result 123, Processing Time 0.02 seconds

Landslide Detection and Landslide Susceptibility Mapping using Aerial Photos and Artificial Neural Networks (항공사진을 이용한 산사태 탐지 및 인공신경망을 이용한 산사태 취약성 분석)

  • Oh, Hyun-Joo
    • Korean Journal of Remote Sensing
    • /
    • v.26 no.1
    • /
    • pp.47-57
    • /
    • 2010
  • The aim of this study is to detect landslide using digital aerial photography and apply the landslide to landslide susceptibility mapping by artificial neural network (ANN) and geographic information system (GIS) at Jinbu area where many landslides have occurred in 2006 by typhoon Ewiniar, Bilis and Kaemi. Landslide locations were identified by visual interpretation of aerial photography taken before and after landslide occurrence, and checked in field. For landslide susceptibility mapping, maps of the topography, geology, soil, forest, lineament, and landuse were constructed from the spatial data sets. Using the factors and landslide location and artificial neural network, the relative weight for the each factors was determinated by back-propagation algorithm. As the result, the aspect and slope factor showed higher weight in 1.2-1.5 times than other factors. Then, landslide susceptibility map was drawn using the weights and finally, the map was validated by comparing with landslide locations that were not used directly in the analysis. As the validation result, the prediction accuracy showed 81.44%.

Prediction and Verification of Water-entry Traces Size of Small Falling Objects into the Sea (해상 소형 낙하물 입수흔적의 크기 예측 및 검증)

  • Min, Anki;Hwang, Tae-Won
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.18 no.2
    • /
    • pp.146-153
    • /
    • 2015
  • An unmanned aerial photography method by using an unmanned helicopter is useful method for measuring of the water-entry traces of small falling objects into the sea. Pixel sizes on the aerial photograph may be too large due to a limit of camcorder resolution and a wide shooting area. If the pixel size is too large, identification of water-entry trace is impossible. Thus an accurate prediction of water-entry trace size is required. The traces of water-entry could be classified into three types such as splash, water column, and bubble. Diameters of each trace are predicted by water-entry impact pressure theories, cavity theories, and trial test results. The results are verified by drop tests using an unmanned helicopter at two water-entry speeds. As a result, prediction and test results showed sufficient similarity to evaluate the identifiability of water-entry trace.

The Research about Aerial photographing system(PKNU No.2) development

  • Kim, Ho-Yong;Choi, Chul-Uong;Lee, Eun-Khung;Jun, Sung-Woo
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.110-112
    • /
    • 2003
  • The researchers, who seek geological and environmental information, depend on the remote sensing and aerial photographic datum from various commercial satellites and aircraft. However, the adverse weather conditions and the expensive equipment can restrict that the researcher can collect their data anywhere and any time. To allow for better flexibility, we have developed a compact, a multispectral automatic Aerial photographic system. This system's Multi-spectral camera can catch the visible (RGB) and infrared (NIR) bands (3032${\ast}$2008 pixel) image. Our system consists of a thermal infrared camera and automatic balance control, and it managed and controlled by a palm-top computer. And it includes a camera gimbals system, GPS receiver, weather sensor and etc. As a result, we have successfully tested its ability to acquire aerial photography, weather data, as well as GPS data, making it a very flexible tool for environmental data monitoring.

  • PDF

A Study on Terrain Construction of Unmanned Aerial Vehicle Simulator Based on Spatial Information (공간정보 기반의 무인비행체 시뮬레이터 지형 구축에 관한 연구)

  • Park, Sang Hyun;Hong, Gi Ho;Won, Jin Hee;Heo, Yong Seok
    • Journal of Korea Multimedia Society
    • /
    • v.22 no.9
    • /
    • pp.1122-1131
    • /
    • 2019
  • This paper covers research on terrain construction for unmanned aerial vehicle simulators using spatial information that was distributed by public institutions. Aerial photography, DEM, vector maps and 3D model data were used in order to create a realistic terrain simulator. A data converting method was suggested while researching, so it was generated to automatically arrange and build city models (vWorld provided) and classification methods so that realistic images could be generated by 3D objects. For example: rivers, forests, roads, fields and so on, were arranged by aerial photographs, vector map (land cover map) and terrain construction based on the tile map used by DEM. In order to verify the terrain data of unmanned aircraft simulators produced by the proposed method, the location accuracy was verified by mounting onto Unreal Engine and checked location accuracy.

A Study on the Optimization Conditions for the Mounted Cameras on the Unmanned Aerial Vehicles(UAV) for Photogrammetry and Observations (무인비행장치용 측량 및 관측용 탑재 카메라의 최적화 조건 연구)

  • Hee-Woo Lee;Ho-Woong Shon;Tae-Hoon Kim
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.26 no.6_2
    • /
    • pp.1063-1071
    • /
    • 2023
  • Unmanned aerial vehicles (UAVs, drones) are becoming increasingly useful in a variety of fields. Advances in UAV and camera technology have made it possible to equip them with ultra-high resolution sensors and capture images at low altitudes, which has improved the reliability and classification accuracy of object identification on the ground. The distinctive contribution of this study is the derivation of sensor-specific performance metrics (GRD/GSD), which shows that as the GSD increases with altitude, the GRD value also increases. In this study, we identified the characteristics of various onboard sensors and analysed the image quality (discrimination resolution) of aerial photography results using UAVs, and calculated the shooting conditions to obtain the discrimination resolution required for reading ground objects.

Evaluation of Possibility for the Classification of River Habitat Using Imagery Information (영상정보를 활용한 하천 서식처 분류 가능성 평가)

  • Lee, Geun-Sang;Lee, Hyun-Seok
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.15 no.3
    • /
    • pp.91-102
    • /
    • 2012
  • As the basis of the environmental ecological river management, this research developed a method of habitat classification using imagery information to understand a distribution characteristics of fish living in a natural river. First, topographic survey and investigation of discharge and water temperature were carried out to analyze hydraulic characteristics of fish habitat, and the unmanned aerial photography was applied to acquire river imagery at the observation time. Riffle, pool, and glide regions were selected as river habitat to analyze fish distribution characteristics. Analysis showed that the standard deviation of RGB on the riffle is higher than pool and glide because of fast stream flow. From the classification accuracy estimation on riffle region according to resolution and kernel size using the characteristics of standard deviation of RGB, the highest classification accuracy was 77.17% for resolution with 30cm and kernel size with 11. As the result of water temperature observation on pool and glide using infrared camera, they were $19.6{\sim}21.3^{\circ}C$ and $15.5{\sim}16.5^{\circ}C$ respectively with the differences of $4{\sim}5^{\circ}C$. Therefore it is possible to classify pool and glide region using the infrared photography information. The habitat classification to figure out fish distribution can be carried out more efficiently, if unmanned aerial photography system with RGB and infrared band is applied.

A Study on the RPC Model Generation from the Physical Sensor Model

  • Kim, Hye-Jin;Kim, Dae-Sung;Lee, Jae-Bin;Kim, Yong-Il
    • Korean Journal of Geomatics
    • /
    • v.2 no.2
    • /
    • pp.139-143
    • /
    • 2002
  • The rational polynomial coefficients (RPC) model is a generalized sensor model that is used as an alternative solution for the physical sensor model for IKONOS of the Space Imaging. As the number of sensors increases along with greater complexity, and the standard sensor model is needed, the applicability of the RPC model is increasing. The RPC model has the advantages in being able to substitute for all sensor models, such as the projective, the linear pushbroom and the SAR. This report aimed to generate a RPC model from the physical sensor model of the KOMPSAT-1(Korean Multi-Purpose Satellite) and aerial photography. The KOMPSAT-1 collects 510~730 nm panchromatic imagery with a ground sample distance (GSD) of 6.6 m and a swath width of 17 km by pushbroom scanning. The least square solution was used to estimate the RPC. In addition, data normalization and regularization were applied to improve the accuracy and minimize noise. This study found that the RPC model is suitable for both KOMPSAT-1 and aerial photography.

  • PDF

Hybrid Communication System for Real-time Video Transmission of Multicopter (멀티콥터의 실시간 영상 전송을 위한 하이브리드 통신 방식)

  • Lee, Sun Yui;Park, Ji Ho;Kim, Jin Young
    • Journal of Satellite, Information and Communications
    • /
    • v.9 no.4
    • /
    • pp.82-86
    • /
    • 2014
  • In this paper, we propose a novel modulation scheme specialized in real time broadcast system using a multicopter. Since multicopters have many advantages in aerial photography, they have been widely used in broadcasting technologies. However, because of restrictions on flight time, it is difficult to utilize multicopters in real time broadcasting systems. Therefore, video transmission using multicopter is necessary for low power communication techniques in air channel environment. Performance results of the hybrid modulation in this paper are compared to that of conventional modulations with Bit Error Rate (BER) and Signal to Noise Ratio (SNR) simulations. The results also showed that proposed system is suitable for aerial photography. Experiments demonstrated the superiority of the proposed modulation scheme by showing received symbols through an USRP equipment.

The Application of Unmanned Aerial Photograpy for Effective Monitoring of Marine Debris (해안표착물의 효율적인 모니터링을 위한 무선 조정 항공기 촬영기법의 적용)

  • Jang, Seon-Woong;Lee, Seong-Kyu;Oh, Seung-Yeol;Kim, Dae-Hyun;Yoon, Hong-Joo
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.17 no.4
    • /
    • pp.307-314
    • /
    • 2011
  • This study proposed detection method of Marine debris using unmanned aerial photography. For unmanned aerial photography, a RC(Radio Control) helicopter which has good movability and economics was used. To a camera mounting, a gimbal equipment was attached to the bottom of the RC helicopter. The gimbal equipment is very useful because it is not seriously affected by vibration and rolling. In addition, we invented that digital image processing algorithm using Matlab program for detection of marine debris from photographs. Particularly, background subtraction in invented algorithm was applied. As a result, marine debris of a variety of forms from different sand states of coast were reliably detected. In the future, monitoring using proposed method was expected to contribute that the solution to representative problem of monitoring area selecting and estimate the total litter mass over the beach. Moreover, It is considered a greater application possibility to marine environmental observations.

Recent R&D Trends of Anti-Drone Technologies (안티 드론 기술 동향)

  • Choi, S.H.;Chae, J.S.;Cha, J.H.;Ahn, J.Y.
    • Electronics and Telecommunications Trends
    • /
    • v.33 no.3
    • /
    • pp.78-88
    • /
    • 2018
  • As the unmanned aerial vehicle industry and its related technologies grow each year, the number of abuse cases caused by drones is increasing. In addition to the invasion of privacy caused by indiscriminate photography, terrorism using unmanned aerial vehicles, which have a low detection probability, high location accuracy, and the capability of targeting people or places, as well as carrying chemicals, radiation materials, and small bombs, is becoming a significant problem around the world. Accordingly, many companies are developing anti-drone solutions that consist of various technologies such as radar, EO/IR cameras, and RF jammers to detect and disable unmanned aerial vehicles. This article briefly introduces the recent R&D trends and technical levels of anti-drone technologies.