Locating and calculating the number of asbestos-cement corrugated roofing tiles is the first step... more Locating and calculating the number of asbestos-cement corrugated roofing tiles is the first step in the demolition process. In this work, archived image cubes of Taiwan served as the fundamental data source used via machine learning approach to identify the existence of asbestos-cement corrugated roofing tiles with more than 85% accuracy. An adequate quantity of ground-truth data covering all the types of roofs via aerial hyperspectral scan was the key to success for this study. Twenty randomly picked samples from the ground-truth group were examined by X-ray refraction detection to ensure correct identification of asbestos-cement corrugated roofing tiles with remote sensing. To improve the classifying accuracy ratio, two different machine learning algorithms were applied to gather the target layers individually using the same universal training model established from 400 ground-truth samples. The agreement portions within the overlapping layers of these two approaches were labeled...
Large and unaccounted numbers of victims in disasters, events, or fires are often trapped in buil... more Large and unaccounted numbers of victims in disasters, events, or fires are often trapped in buildings or debris, and must be located and rescued as soon as possible. This study transforms smartphones into indoor locating tools without extra modification or complicated program installation, considering smartphones are likely to be carried when disasters strike. The study creates a system that converts smartphones into a lifesaving tool for trapped victims and rescuers. This study employs the Bluetooth beacon in smartphones to send signals using its low power consumption feature. The signal could continue transmitting for rescuers to locate trapped victims for longer. Rescuers could use the Bluetooth function on a regular notebook computer to search such signals without any hardware implementation or modification, allowing them to locate and determine the position of many trapped victims simultaneously. Implementing this system will decrease the search and rescue team’s need to enter...
This study determines the energy usage pattern for Penghu, which is an island in the Taiwan Strai... more This study determines the energy usage pattern for Penghu, which is an island in the Taiwan Strait, for which electricity is the major energy source. There is an increase in electricity consumption as the number of inhabitants and tourists increases. Water supply from desalination plants represents another major electricity demand. To reduce energy consumption and carbon emissions, subsidy programs are used to encourage the use of LED lighting and energy-efficient appliances (air conditioners and refrigerators), but not for common appliances, such as chest freezers. Abundant solar radiation in summer and the northeast monsoon in autumn/winter make Penghu an ideal location to take advantage of solar energy and wind power. An undersea cable between Penghu and Taiwan is now available and can be used to stabilize the isolated grid system in Penghu. The target for a low-carbon island can be achieved by installing PV systems and onshore and offshore wind turbines to fulfill the energy dem...
Presented in the First Meeting of Special Study Group 4.176 (Models of temporal variations of the... more Presented in the First Meeting of Special Study Group 4.176 (Models of temporal variations of the gravity field) of the International Association of Geodesy
Post chemical engineering of crude Au nanoparticles on a soft substrate using a gentle reductant ... more Post chemical engineering of crude Au nanoparticles on a soft substrate using a gentle reductant for radioactive growth to promote SERS amplification.
The 21 September 1999 Chi-Chi, Taiwan, earthquake of magnitude M W = 7.6 (M L = 7.3) severely def... more The 21 September 1999 Chi-Chi, Taiwan, earthquake of magnitude M W = 7.6 (M L = 7.3) severely deformed the Earth's crust in the central Taiwan region. The earthquake created an 85-km-long surface rupture along the Chelungpu fault. The epicenter was located at 23.85 • N, 120.81 • E, near the southern end of the rupture zone. Threedimensional displacements of 285 geodetic control stations were determined in this study from Global Positioning System (GPS) observations collected before and after the earthquake. The detailed surface displacement field shows that individual stations are vertically uplifted by up to 4 m and displaced horizontally by up to 9 m, with the largest displacement occurring near the northern end of the ruptured thrust fault. The azimuth of the surface displacement field is approximately parallel to the direction of tectonic convergence of the Eurasian and Philippine Sea plates. The maximum three-dimensional displacement of 9.9 m is among the largest fault movements ever measured for modern earthquakes.
In the paper "Horizontal viscoelastic-gravitational displacement due to a rectangular dipping thr... more In the paper "Horizontal viscoelastic-gravitational displacement due to a rectangular dipping thrust fault in a layered Earth model" by Josd Fernfindez, Ting-To Yu and John B. Rundle (Journal of Geophysical Research, 101(B6), 13,581-13,594, 1996) we have found two mistakes while using the method for calculating horizontal deformations produced by thrust faulting in viscoelasticgravitational layered Earth models.
Viscoelastic modeling of earthquakes in the sou,•heast Caribbem• shows that distant dip-slip eart... more Viscoelastic modeling of earthquakes in the sou,•heast Caribbem• shows that distant dip-slip earthquakes in the Lesser Antilles and the geometry of the subduction zone play a significant role in vertical deformation observed along the southern Caribbean plate margin. We f'md that dip-slip earthq•es yield vertical displacements that are 1-2 orders of magnitude greater than those generated by strike-slip earthquakes along the Caribbean-South American plate boundary. In addition, postseismic vertical displacements are at least as great or greater at distances of several hundred kilometers than the coseismic counterpart depending upon the geometry of the source. Tide gage data from Venezuela suggest that these vertical displacement rates may still be obse•x, ed several decades after the occurrence of large subduction zone earthquakes (Ms 7 or greater). In addition, the uplift rate observed at the tide gages largely follows the anticipated flexure of the Caribbean plate due to the subduction process. Interseismic deformation near subduction zones has been observed with tide gages in Japan [Savage and Plajker, 1991; Savage and Thatcher, 1992], Chile [Barrientos et al., 1992], and Alaska [Wahr and Wyss, 1980]. These deformations can also be seen in leveling data from the Pacific northwest of the United States [e.g., HoldaM et al., 1987] and Alaska [Brown et al., 1977]. Here we address the southeast Caribbean which involves the intersection of a major transform fault with a subduction zone. Earthquake focal mechanisms [e.g., Pdrez and Aggarwal, 1981; Russo et al., 1993], gravity anomalies
The 80-km-long surface rupture of the Chelungpu fault in the 21 September 1999, Chichi, Taiwan Mw... more The 80-km-long surface rupture of the Chelungpu fault in the 21 September 1999, Chichi, Taiwan Mw=7.6 earthquake resulted in a surface scarp with vertical throws of 2±9 m, and horizontal heaves of 4±8 m. Few major thrust faults have broken the surface in the past century, and the Chelungpu surface rupture is of interest in that it provides a morphological template for the identi®cation of paleo-surface thrusts in similar neotectonic environments such as the Himalaya. The toe of the thrust is found emplaced gently over underlying hanging-wall materials, partly by prograde hanging-wall rotation and partly by simple shear, leaving few overt clues as to the total amount or sense of slip. Despite the large surface slip near the toe of the Chelungpu thrust its emplacement appears to have been relatively slow. MSK (the Medvedev±Sponheuer±Karnik 1981 revision of the Seismic Intensity Scale MSK81 supersedes the Mercalli Intensity scale for the description of acceleration-induced damage to modern buildings) Intensity VIII accelerations were imposed on buildings on the hanging-wall, and Intensity VII on the footwall, decaying in both directions by perhaps one intensity unit a few hundred meters from the rupture. The somewhat moderate amplitude of these accelerations, for a rupture with several meters of slip, is attributed to non-linear dissipative deformation near the toe of the rupture. The partitioning of thrusting into basal slip and hillside steepening in some locations on the Chelungpu fault suggests that the estimation of paleoseismic slip from the oset of piercing points crossing historic thrust faults elsewhere may result in underestimates of fault slip.
The theoretical and computational methods for the calculation of viscoelastic-gravitational displ... more The theoretical and computational methods for the calculation of viscoelastic-gravitational displacements resulting from strike-slip faulting in a layered Earth model were described. We considered a medium composed of one elastic-gravitational layer over a viscoelastic-gravitational half-space. The FORTRAN programs STRGRV and STRGRH used to compute vertical and horizontal displacement, respectively, are described. Some examples of computed displacements with various parameters are presented.
Natural selection is the spirit of the genetic algorithm (GA): by keeping the good genes in the c... more Natural selection is the spirit of the genetic algorithm (GA): by keeping the good genes in the current generation, thereby producing better offspring during evolution. The crossover function ensures the heritage of good genes from parent to offspring. Meanwhile, the process of mutation creates a special gene, the character of which does not exist in the parent generation. A program
Due to several reasons, there is a shortage of water resources in Taiwan, despite abundant rainfa... more Due to several reasons, there is a shortage of water resources in Taiwan, despite abundant rainfall. These reasons include high population density, uneven spatial and temporal distribution of rainfall, and rivers with steep gradients. According to the data collected by Central Geological Survey in the project: Pumping of Groundwater Resources in the Central Division of Mountain Areas of Taiwan, the abundant underground water in mountain areas exists in areas with thick regolith, broken rock or sandstone. Therefore, the investigation of regolith depth distribution would help us to further understand the amount of underground water, and the areas that can be exploited. This study is based on 441 drilling data over the Da-Chia and Choshui river basins, and aims to construct a relation model of topographic and environmental variables and to estimate the regolith depth in the study area. The amount of drilling data will be increased each year so that the model can be improved, developed ...
Landslides have been identified as one of the costliest and deadliest natural disasters, causing ... more Landslides have been identified as one of the costliest and deadliest natural disasters, causing tremendous damage to humans and societies. Information regarding the spatial extent of landslides is thus important to allow officials to devise successful strategies to mitigate landslide hazards. This study aims to develop a machine-learning approach for predicting landslide areas in the Tsengwen River Watershed (TRW), which is one of the most landslide-prone areas in Central Taiwan. Various spatial datasets were collected from 2009 to 2015 to derive 36 predictive variables used for landslide modeling with random forests (RF). The results of landslide prediction, compared with ground reference data, indicated an overall accuracy of 91.4% and Kappa coefficient of 0.83, respectively. The findings achieved from estimates of predictor importance also indicated to officials that the land-use/land-cover (LULC) type, distance to previous landslides, distance to roads, bank erosion, annual gro...
Aerial photos with LiDAR data were processed with genetic algorithms for not only the feature ext... more Aerial photos with LiDAR data were processed with genetic algorithms for not only the feature extraction but also orthographical image. DSM provided by LiDAR reduced the amount of GCPs needed for the regular processing, thus the reason both of the efficiency and accuracy are highly improved. Keywords--- GA, LiDAR, Feature Extraction. 1.
Precise and also up-to-date terrain information is very precious and also expensive, too. For the... more Precise and also up-to-date terrain information is very precious and also expensive, too. For the active geological hazard regime like Taiwan or Japan, the change of terrain associated with particular event reached to the level of meter or even tens of meters which enhance the importance of the data processing in regarding to the DTM at both accuracy and efficiency issues. Aerial LiDAR could gather both the DSM and DEM simultaneously, it also provide the intensity map of reflected laser strength that serves as a black & white base image map. On the other hand, photogrammetry not only relies on the quality of aerial photos or satellite images but also the skill of operators. Human error in DTM manufactory process is inevitable and it is also affected by the land cover, roughness of terrain etc. DTM of three regions at Taiwan gathered with LiDAR and also photogrammetry with the same SOP are compared, systematic discrepancy between these two data set have been identified as the functio...
Taiwan mountains are severely affected each year by landslides, rock falls, and debris flows wher... more Taiwan mountains are severely affected each year by landslides, rock falls, and debris flows where the roads system suffer the most critical consequences. Among all mountain highways, Ali Highway, located into the main entrance of Alishan Mountain region, is one of the most landslide-prone areas in southern Taiwan. During the typhoon season, between May and August, the probability of occurrence of mass movements is at higher level than usual seeing great erosion rates. In fact, during Typhoon Morakot, in 2009, the intense rainfall caused abrupt interruption of the circulation for three months triggering several landslides (Liu et al. 2012). The topographic features such as slope, roughness and curvature among others have been extracted from 1 m DTM derived by a LiDAR dataset (collected in 2015) to investigate the slope failures along the Ali Mountain Highway. The high-resolution DTM highlighted that the hydrogeomorphological (e.g. density of stream, the distance from the ridge and t...
Locating and calculating the number of asbestos-cement corrugated roofing tiles is the first step... more Locating and calculating the number of asbestos-cement corrugated roofing tiles is the first step in the demolition process. In this work, archived image cubes of Taiwan served as the fundamental data source used via machine learning approach to identify the existence of asbestos-cement corrugated roofing tiles with more than 85% accuracy. An adequate quantity of ground-truth data covering all the types of roofs via aerial hyperspectral scan was the key to success for this study. Twenty randomly picked samples from the ground-truth group were examined by X-ray refraction detection to ensure correct identification of asbestos-cement corrugated roofing tiles with remote sensing. To improve the classifying accuracy ratio, two different machine learning algorithms were applied to gather the target layers individually using the same universal training model established from 400 ground-truth samples. The agreement portions within the overlapping layers of these two approaches were labeled...
Large and unaccounted numbers of victims in disasters, events, or fires are often trapped in buil... more Large and unaccounted numbers of victims in disasters, events, or fires are often trapped in buildings or debris, and must be located and rescued as soon as possible. This study transforms smartphones into indoor locating tools without extra modification or complicated program installation, considering smartphones are likely to be carried when disasters strike. The study creates a system that converts smartphones into a lifesaving tool for trapped victims and rescuers. This study employs the Bluetooth beacon in smartphones to send signals using its low power consumption feature. The signal could continue transmitting for rescuers to locate trapped victims for longer. Rescuers could use the Bluetooth function on a regular notebook computer to search such signals without any hardware implementation or modification, allowing them to locate and determine the position of many trapped victims simultaneously. Implementing this system will decrease the search and rescue team’s need to enter...
This study determines the energy usage pattern for Penghu, which is an island in the Taiwan Strai... more This study determines the energy usage pattern for Penghu, which is an island in the Taiwan Strait, for which electricity is the major energy source. There is an increase in electricity consumption as the number of inhabitants and tourists increases. Water supply from desalination plants represents another major electricity demand. To reduce energy consumption and carbon emissions, subsidy programs are used to encourage the use of LED lighting and energy-efficient appliances (air conditioners and refrigerators), but not for common appliances, such as chest freezers. Abundant solar radiation in summer and the northeast monsoon in autumn/winter make Penghu an ideal location to take advantage of solar energy and wind power. An undersea cable between Penghu and Taiwan is now available and can be used to stabilize the isolated grid system in Penghu. The target for a low-carbon island can be achieved by installing PV systems and onshore and offshore wind turbines to fulfill the energy dem...
Presented in the First Meeting of Special Study Group 4.176 (Models of temporal variations of the... more Presented in the First Meeting of Special Study Group 4.176 (Models of temporal variations of the gravity field) of the International Association of Geodesy
Post chemical engineering of crude Au nanoparticles on a soft substrate using a gentle reductant ... more Post chemical engineering of crude Au nanoparticles on a soft substrate using a gentle reductant for radioactive growth to promote SERS amplification.
The 21 September 1999 Chi-Chi, Taiwan, earthquake of magnitude M W = 7.6 (M L = 7.3) severely def... more The 21 September 1999 Chi-Chi, Taiwan, earthquake of magnitude M W = 7.6 (M L = 7.3) severely deformed the Earth's crust in the central Taiwan region. The earthquake created an 85-km-long surface rupture along the Chelungpu fault. The epicenter was located at 23.85 • N, 120.81 • E, near the southern end of the rupture zone. Threedimensional displacements of 285 geodetic control stations were determined in this study from Global Positioning System (GPS) observations collected before and after the earthquake. The detailed surface displacement field shows that individual stations are vertically uplifted by up to 4 m and displaced horizontally by up to 9 m, with the largest displacement occurring near the northern end of the ruptured thrust fault. The azimuth of the surface displacement field is approximately parallel to the direction of tectonic convergence of the Eurasian and Philippine Sea plates. The maximum three-dimensional displacement of 9.9 m is among the largest fault movements ever measured for modern earthquakes.
In the paper "Horizontal viscoelastic-gravitational displacement due to a rectangular dipping thr... more In the paper "Horizontal viscoelastic-gravitational displacement due to a rectangular dipping thrust fault in a layered Earth model" by Josd Fernfindez, Ting-To Yu and John B. Rundle (Journal of Geophysical Research, 101(B6), 13,581-13,594, 1996) we have found two mistakes while using the method for calculating horizontal deformations produced by thrust faulting in viscoelasticgravitational layered Earth models.
Viscoelastic modeling of earthquakes in the sou,•heast Caribbem• shows that distant dip-slip eart... more Viscoelastic modeling of earthquakes in the sou,•heast Caribbem• shows that distant dip-slip earthquakes in the Lesser Antilles and the geometry of the subduction zone play a significant role in vertical deformation observed along the southern Caribbean plate margin. We f'md that dip-slip earthq•es yield vertical displacements that are 1-2 orders of magnitude greater than those generated by strike-slip earthquakes along the Caribbean-South American plate boundary. In addition, postseismic vertical displacements are at least as great or greater at distances of several hundred kilometers than the coseismic counterpart depending upon the geometry of the source. Tide gage data from Venezuela suggest that these vertical displacement rates may still be obse•x, ed several decades after the occurrence of large subduction zone earthquakes (Ms 7 or greater). In addition, the uplift rate observed at the tide gages largely follows the anticipated flexure of the Caribbean plate due to the subduction process. Interseismic deformation near subduction zones has been observed with tide gages in Japan [Savage and Plajker, 1991; Savage and Thatcher, 1992], Chile [Barrientos et al., 1992], and Alaska [Wahr and Wyss, 1980]. These deformations can also be seen in leveling data from the Pacific northwest of the United States [e.g., HoldaM et al., 1987] and Alaska [Brown et al., 1977]. Here we address the southeast Caribbean which involves the intersection of a major transform fault with a subduction zone. Earthquake focal mechanisms [e.g., Pdrez and Aggarwal, 1981; Russo et al., 1993], gravity anomalies
The 80-km-long surface rupture of the Chelungpu fault in the 21 September 1999, Chichi, Taiwan Mw... more The 80-km-long surface rupture of the Chelungpu fault in the 21 September 1999, Chichi, Taiwan Mw=7.6 earthquake resulted in a surface scarp with vertical throws of 2±9 m, and horizontal heaves of 4±8 m. Few major thrust faults have broken the surface in the past century, and the Chelungpu surface rupture is of interest in that it provides a morphological template for the identi®cation of paleo-surface thrusts in similar neotectonic environments such as the Himalaya. The toe of the thrust is found emplaced gently over underlying hanging-wall materials, partly by prograde hanging-wall rotation and partly by simple shear, leaving few overt clues as to the total amount or sense of slip. Despite the large surface slip near the toe of the Chelungpu thrust its emplacement appears to have been relatively slow. MSK (the Medvedev±Sponheuer±Karnik 1981 revision of the Seismic Intensity Scale MSK81 supersedes the Mercalli Intensity scale for the description of acceleration-induced damage to modern buildings) Intensity VIII accelerations were imposed on buildings on the hanging-wall, and Intensity VII on the footwall, decaying in both directions by perhaps one intensity unit a few hundred meters from the rupture. The somewhat moderate amplitude of these accelerations, for a rupture with several meters of slip, is attributed to non-linear dissipative deformation near the toe of the rupture. The partitioning of thrusting into basal slip and hillside steepening in some locations on the Chelungpu fault suggests that the estimation of paleoseismic slip from the oset of piercing points crossing historic thrust faults elsewhere may result in underestimates of fault slip.
The theoretical and computational methods for the calculation of viscoelastic-gravitational displ... more The theoretical and computational methods for the calculation of viscoelastic-gravitational displacements resulting from strike-slip faulting in a layered Earth model were described. We considered a medium composed of one elastic-gravitational layer over a viscoelastic-gravitational half-space. The FORTRAN programs STRGRV and STRGRH used to compute vertical and horizontal displacement, respectively, are described. Some examples of computed displacements with various parameters are presented.
Natural selection is the spirit of the genetic algorithm (GA): by keeping the good genes in the c... more Natural selection is the spirit of the genetic algorithm (GA): by keeping the good genes in the current generation, thereby producing better offspring during evolution. The crossover function ensures the heritage of good genes from parent to offspring. Meanwhile, the process of mutation creates a special gene, the character of which does not exist in the parent generation. A program
Due to several reasons, there is a shortage of water resources in Taiwan, despite abundant rainfa... more Due to several reasons, there is a shortage of water resources in Taiwan, despite abundant rainfall. These reasons include high population density, uneven spatial and temporal distribution of rainfall, and rivers with steep gradients. According to the data collected by Central Geological Survey in the project: Pumping of Groundwater Resources in the Central Division of Mountain Areas of Taiwan, the abundant underground water in mountain areas exists in areas with thick regolith, broken rock or sandstone. Therefore, the investigation of regolith depth distribution would help us to further understand the amount of underground water, and the areas that can be exploited. This study is based on 441 drilling data over the Da-Chia and Choshui river basins, and aims to construct a relation model of topographic and environmental variables and to estimate the regolith depth in the study area. The amount of drilling data will be increased each year so that the model can be improved, developed ...
Landslides have been identified as one of the costliest and deadliest natural disasters, causing ... more Landslides have been identified as one of the costliest and deadliest natural disasters, causing tremendous damage to humans and societies. Information regarding the spatial extent of landslides is thus important to allow officials to devise successful strategies to mitigate landslide hazards. This study aims to develop a machine-learning approach for predicting landslide areas in the Tsengwen River Watershed (TRW), which is one of the most landslide-prone areas in Central Taiwan. Various spatial datasets were collected from 2009 to 2015 to derive 36 predictive variables used for landslide modeling with random forests (RF). The results of landslide prediction, compared with ground reference data, indicated an overall accuracy of 91.4% and Kappa coefficient of 0.83, respectively. The findings achieved from estimates of predictor importance also indicated to officials that the land-use/land-cover (LULC) type, distance to previous landslides, distance to roads, bank erosion, annual gro...
Aerial photos with LiDAR data were processed with genetic algorithms for not only the feature ext... more Aerial photos with LiDAR data were processed with genetic algorithms for not only the feature extraction but also orthographical image. DSM provided by LiDAR reduced the amount of GCPs needed for the regular processing, thus the reason both of the efficiency and accuracy are highly improved. Keywords--- GA, LiDAR, Feature Extraction. 1.
Precise and also up-to-date terrain information is very precious and also expensive, too. For the... more Precise and also up-to-date terrain information is very precious and also expensive, too. For the active geological hazard regime like Taiwan or Japan, the change of terrain associated with particular event reached to the level of meter or even tens of meters which enhance the importance of the data processing in regarding to the DTM at both accuracy and efficiency issues. Aerial LiDAR could gather both the DSM and DEM simultaneously, it also provide the intensity map of reflected laser strength that serves as a black & white base image map. On the other hand, photogrammetry not only relies on the quality of aerial photos or satellite images but also the skill of operators. Human error in DTM manufactory process is inevitable and it is also affected by the land cover, roughness of terrain etc. DTM of three regions at Taiwan gathered with LiDAR and also photogrammetry with the same SOP are compared, systematic discrepancy between these two data set have been identified as the functio...
Taiwan mountains are severely affected each year by landslides, rock falls, and debris flows wher... more Taiwan mountains are severely affected each year by landslides, rock falls, and debris flows where the roads system suffer the most critical consequences. Among all mountain highways, Ali Highway, located into the main entrance of Alishan Mountain region, is one of the most landslide-prone areas in southern Taiwan. During the typhoon season, between May and August, the probability of occurrence of mass movements is at higher level than usual seeing great erosion rates. In fact, during Typhoon Morakot, in 2009, the intense rainfall caused abrupt interruption of the circulation for three months triggering several landslides (Liu et al. 2012). The topographic features such as slope, roughness and curvature among others have been extracted from 1 m DTM derived by a LiDAR dataset (collected in 2015) to investigate the slope failures along the Ali Mountain Highway. The high-resolution DTM highlighted that the hydrogeomorphological (e.g. density of stream, the distance from the ridge and t...
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