Cloud covers are generally present in optical remote-sensing images, which limit the usage of acquired images. In previous studies, thresholding is a common and rapid method in cloud detection. However, a selected threshold is usually suitable for local study areas, and it may be failed in other cases. Besides, there are many exceptions to control, and the environment is changed dynamically. In this study, a threshold-free method based on Support Vector Machine (SVM) is proposed, which can avoid the abovementioned problems. A statistical model is adopted to detect clouds instead of a subjective thresholding-based method. According to the physical characteristics of clouds and other objects, the spectral features are appropriately designed for classification. Spatial and temporal information are also important for satellite images. Consequently, co-occurrence matrix of the Hotelling transform is used in proposed method. Experiment results demonstrate the detection accuracy of the proposed method is about 93% to 97%.

This paper investigates the shoreline evolution of Waisanding barrier using waterline detection from satellite images. Required image processing includes (1) IHS conversion method (2) NDWI index (3) Image enhancement method (4) Morphology and (5) Canny edge detection for capturing the waterline. Due to no observation on tides at the Waisanding barrier data blending method associated with NAO99b tidal model is used to accurately compute the tidal levels. The horizontal distance to shift the waterline to the shoreline is determined by both obtained tidal level and beachface slope. The shoreline evolution and land-area variation above mean sea level of the Waisanding barrier from 1994 to 2015 are evaluated to show that the northern shoreline of the Waisanding barrier is receding by a rate of 30.5 m/yr and the southern part is by 119 m/yr. The results also indicate that the land area of the Waisanding barrier has a long-term decreasing trend with a faster rate in the recent period and a regular and seasonal variation of erosion in the winter and accretion in the summer. Depending on the decreasing rate of land area from 2009 to 2015 the Waisanding barrier will vanish in 2060 based on the rate.

There are many pollutants in the air. Particulate Matter (PM) is similar to floating dust. For those with size less than or equal to 2.5μm, they are called PM2.5 (Taiwan EPA, 2015). The concentration of PM2.5 is an important indicator of air condition. By 2014, there are 73 PM2.5 monitoring stations established by the Environmental Protection Administration (EPA) in Taiwan. While the ground stations provide continuous and high precision in-situ observations, satellite borne remote sensing technique could provide a vast area coverage but with limited time epoch information. Among a number of satellite image sensors, MODIS provides a standard scientific product, MOD04, for AOD (Aerosol Optical Depth, AOD) measurement. With MOD04, PM2.5 concentration could be estimated with correlation and regression to in-situ measurements. This study utilized the 73 EPA ground stations for an incidence occurred on Feb. 14, 2013 in the 6th naphtha cracker of Formosa Plastic Group. The result shows that the correlation index R2 between AOD and PM2.5 is 0.50 among Taiwan. According to the 5 ground in situ PM2.5 data nearby the 6th naphtha cracker, they are all up to 54μm/m3 and have exceeded the EPA standard of 35μm/m3 the air quality standard per 24 hours. While the AOD measurements derived from satellite images offer a way for estimating PM2.5 concentrations, further improvement in the modeling and data processing is required for reducing the uncertainty.

In this study, the underwater photogrammetry and object tracking techniques are adopted for monitoring the 6 Degree-of-Freedom (6DOF) dynamic change of an Elephant Trunk Steel Pipe (ETSP) scale model during its underwater installation simulation, and then reconstruct its 4D animation by integrating its 3D model and 6DOF parameters. Considering the difficulty of camera installation in the underwater environment, the 3D model based object tracking technic is adopted to compute the positions and attitudes of camera instead of tracking feature points on objects. Under the concept of relative motion, the 6DOF parameters of ETSP can be obtained through multi-camera coordinate transformation or single camera relative orientation transformation if their orientation parameters are calculated by space resection. Results and analysis show that both multi-camera and single camera approaches can derive the 6DOF parameters of ETSP, in which single camera approach shows higher convenience that has benefits of low cost and high efficiency.

The goal of this study is to develop a formation flight simulation platform for Unmanned Aerial Vehicles (UAVs). By using the developed platform, the formation flight control for multi-agent system can be designed and simulated. The multi-agent system comprises of more than one physically independent agent while having a common goal. The main tasks in this study contain formation flight navigation and control and navigation, formation scheme and algorithm development, Hardware-In-the-Loop (HIL) system setup, and flight simulation and verification. The adopted UAVs include fixed-wing and rotorcraft types. The quad-rotor UAV was selected to be the target aircraft for rotorcraft. This study successfully performed the formation flight controller and algorithm on the developed HIL platform. The results show that both the fixed-wing UAV and rotorcraft can be simulated on this platform.