• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.522-525
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• 2007

Frame Synchronization is applied to not only digital data transmission for data synchronization between transmitter and receiver but also data communication with satellite. When satellite image data with high resolution and mass storage is transmitted, hardware frame synchronizer for real-time processing or software frame synchronizer for post-processing is used. In case of hardware, processing with high speed is available but data loss may happen for Search of Frame Synchronization. In case of software, data loss does not happen but speed is relatively slow. In this paper, Pending Buffer concept was proposed to cope with data loss according to processing status of Frame Synchronization. Algorithm to process Frame synchronization with high speed using bit threshold search algorithm with pattern search technique and SIMD is also proposed.

• 대한원격탐사학회지
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• 제19권3호
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• pp.247-253
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• 2003

The mainly used technique to correct satellite images with geometric distortion is to develop a mathematical relationship between pixels on the image and corresponding points on the ground. Polynomial models with various transformations have been designed for defining the relationship between two coordinate systems. GCP based geometric correction has peformed overall plane to plane mapping. In the overall plane mapping, overall structure of a scene is considered, but local variation is discarded. The Region with highly variant height is rectified with distortion on overall plane mapping. To consider locally variable region in satellite image, TIN-based rectification on a satellite image is proposed in this paper. This paper describes the relationship between GCP distribution and rectification model through experimental result and analysis about each rectification model. We can choose a geometric correction model as the structural characteristic of a satellite image and the acquired GCP distribution.

• 한국항공운항학회지
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• 제15권2호
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• pp.1-8
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• 2007

In this research, algorithm and software for the medium frequency signal analysis of DGPS(Differential Global Positioning System) station were developed. Based on new MF(Medium Frequency) algorithm, the software of NDGPS(National DGPS) signal analysis was developed for coverage analysis. Predicted MF propagation data from this software was compared to the measurement data for the verification of a developed MF algorithm. GIS(Geographic Information System) techniques including digital map with elevation data were used because MF propagation is closely related to ground conductivity, mountains, building intensity.

• 항공우주시스템공학회지
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• 제6권4호
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• pp.34-39
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• 2012

CubeSats classified as pico-class satellite require a ground station to track the satellite, transmit a command, and receive an on-orbit data such as SOH (State-of-Health) and mission data according to the operation plan. For this, ground station system has to be properly designed to perform a communication to with the satellite with enough up- and down-link budgets. In this study, a conceptual design of the ground station has been performed for the CubeSat named as STEP Cube Lab. (Cube Laboratory for Space Technology Experimental Project). The paper includes a ground station hardware interface design, link budget analysis and a ground station software realization. In addition, the operation plan of the ground station has been established considering the STEP Cube Lab. mission requirements.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.529-536
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• 2002

The purpose of this paper os to present and discuss some of flow and drain observed in modelling results. Because dredged fill ground of Yul-Chon located in the south coast of Korea is very soft, this ground should be improved after operation of surface stabilization. There are surface stabilization method such as chemical stabilization, desiccation, horizontally vacuum drain, replacement, and geosynthetics. In Yul-Chon, PTM(Progressive Trenching Method) is adopted to provide the necessity condition of surface desiccation. In the case trench in the dredged soft ground is formed by PTM equipment, pore water in the ground is drained through trench. There, drain and desiccation of surface ground increase, and bearing capacity is improved. In this research, when trench in the dredged soft ground is formed by PTM equipment, permeable characteristics and drain efficiency of pore-water are analyzed using SEEP/W software package. Results show variation of total head, pressure head, flux, hydraulic gradient, and flow quantity.

• 한국인터넷방송통신학회논문지
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• 제21권6호
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• pp.111-116
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• 2021

초분광 영상은 적외선 영역의 전자기파 대역을 수백 개의 파장으로 나누어 영상화한 데이터로 다양한 분야에서 물체를 찾거나 분류하는 것에 활용된다. 최근에는 딥러닝을 사용하여 분류하는 방법이 주목받고 있지만 초분광 영상 데이터의 특성으로 인해 초분광 영상을 학습 데이터로 사용하기 위해서는 기존의 가시광 영상과는 다른 처리 기법이 필요하다. 이를 위해 초분광 큐브에서 특정 파장의 영상을 선택하여 Ground Truth 작업을 수행하고 환경정보를 포함하여 데이터를 관리하는 소프트웨어를 개발하였다. 본 논문에서는 해당 소프트웨어의 구성과 기능에 대하여 설명한다.

• 한국위성정보통신학회논문지
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• 제3권2호
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• pp.32-37
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• 2008

Global Navigation Satellite System (GNSS) is been developing in many countries. The satellite navigation system has the importance in economic and military fields. For utilizing satellite navigation system properly, the technology of GNSS Ground Station is needed. GNSS Ground Station monitors the signal of navigation satellite and analyzes navigation solution. This study deals with the navigation software for GNSS Ground Station. This paper will introduce the navigation solution algorithm for GNSS Ground Station. The navigation solution can be calculated by the code-carrier smoothing method, the Kalman-filter method, the least-square method, and the weight least square method. The performance of each navigation algorithm in this paper is presented.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 춘계학술대회 논문집
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• pp.269-275
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• 2000

The railway signaling system consists of microcomputerized vital devices on board and ground, which are connected to one another by track circuits, and interlocking equipment for route control. Therefore it is important to validate the required functions of developed system and interface between developed signaling systems. To verify the conditions and functions of signaling logic, the laboratory prototype test bench, which consists of personal computers with software module and Ethernet LAN, will be developed. In this paper general design of signaling system test bench for high-speed rail is described and developed software module is presented.

• 토지주택연구
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• 제8권1호
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• pp.13-22
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• 2017

In this study, triggering mechanism of ground sinking was analyzed through groundwater flow analysis on the basis of a case of the ground sinking occurred in Yongsan in 2015. The results of geotechnical investigation performed before and after the ground sinking were analyzed for the accurate understanding of geological features in the study area. The numerical groundwater flow analysis was performed to evaluate the influence of the flow behavior from the surrounding area toward the excavated site using software of Visual MODFLOW. As a result, it was found from the geotechnical analysis that the strata of sedimentary layer along the sunken area in the vertical direction was mixed significantly after the ground sinking compared with the status of the soil condition before the ground sinking. Piping was occurred at the toe of cut-off wall in the sandy gravel layer, and this phenomenon was predicted by the numerical flow analysis. Sequential ground displacement scenario of the ground sinking was derived from the geotechnical in situ test and numerical flow analysis performed in this study.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.130-133
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• 2007

In order to get high quality and high resolution image data from the space-borne camera system, the image chain from the sensor to the user in the ground-station need to be designed and controlled with extreme care. The behavior of the camera system needs to be controlled by ground commands to support on-orbit calibration and to adjust imaging parameters and to perform early stage on-orbit image correction, like gain and offset control, non-uniformity correction, etc. The operation status including the temperature of the sensor needs to be transferred to the ground-station. The preparation time of the camera system for imaging with specific parameters should be minimized. The camera controller needs to synchronize the operation of cameras for every channel and for every spectral band. Detail timing information of the image data needs to be provided for image data correction at ground-station. In this paper, the design of the camera controller for the AEISS on KOMPSAT-3 will be introduced. It will be described how the image chain is controlled and which imaging parameters are to be adjusted The camera controller will have software for the flexible operation of the camera by the ground-station operators and it can be reconfigured by ground commands. A simple concept of the camera operations and the design of the camera controller, not only with hardware but also with controller software are to be introduced in this paper.