Since 2002, the Soil and Water Conservation Bureau, which is responsible for the conservation and administrative management of hillside in Taiwan, has been cooperating with Feng Chia University. Together, they have su...Since 2002, the Soil and Water Conservation Bureau, which is responsible for the conservation and administrative management of hillside in Taiwan, has been cooperating with Feng Chia University. Together, they have successfully carried out the establishment and maintenance of 13 fixed debris flow monitoring stations over the island and 2 mobile debris flow monitoring stations. During July 2004, a powerful southwest air current brought by Mindulle Typhoon caused serious flood in central and southern Taiwan. This paper aims to describe the establishment of debris flow monitoring systems in Taiwan and the observation of the debris flow event during Mindulle Typhoon at Aiyuzi River in Shenmu Village, Nantou County by the monitoring station.展开更多
Liquid composite moulding (LCM) processes are used to manufacture high quality and complex-shaped composite parts in the automotive, marine, aerospace and civil industries. On-line sensing plays an important role in c...Liquid composite moulding (LCM) processes are used to manufacture high quality and complex-shaped composite parts in the automotive, marine, aerospace and civil industries. On-line sensing plays an important role in controlling the quality of the final product in the LCM manufacturing environment. The long-period fiber grating (LPG) technology, a new real-time fiber optic sensor system, was developed to monitor the flow front progression. The sensor operation and characterization under various process conditions were discussed in detail. The experimental results showed that LPG sensors were robust and reliable to detect the arrival of resin at pre-selected locations in structures with low-medium fiber volume fraction; however were limited at different depths in structures with high fiber volume fraction.展开更多
Laser speckle imaging is a common technique to monitor blood flow.The fluctuations in speckle intensity can be related to the blood flow by calculating the speckle contrast,the ratio between the standard deviation of ...Laser speckle imaging is a common technique to monitor blood flow.The fluctuations in speckle intensity can be related to the blood flow by calculating the speckle contrast,the ratio between the standard deviation of speckle fluctuations and the average intensity.However,this simple statistic calculation is easily affected by motion artifacts.In this study,we applied sample entropy analysis instead of calculating standard deviations of the speckle fluctuations.Similar to the traditional method,sample entropy-based speckle contrast increases linearly with flow rate but was shown to be more immune to sudden movements during an upper arm occlusion test.展开更多
Convenient non-invasive flow monitoring would facilitate the operation and control in microfluidic chips,but is challenging due to the small space of microchannels and complex operation required in traditional optical...Convenient non-invasive flow monitoring would facilitate the operation and control in microfluidic chips,but is challenging due to the small space of microchannels and complex operation required in traditional optical methods.In this work,we propose a novel non-invasive strategy to probe microfluidic flows via streaming potential phenomenon.By sealing one side of the microchannel with a piece of hydrogel film,streaming potential inside the channel can be clearly detected by electrodes at outer surface of the hydrogel due to ion diffusion in the hydrogel.Flow is detected without sensors contacting with the internal liquid.Moreover,the electrodes shape like a tiny probe,which can move around mapping the flow distribution in a chip with the spatial resolution of 1 mm and flow rate detection limit of 3μL·min–1.Bubbles inside the channels can also be detected,due to the fluctuation of streaming voltage when gas-liquid interface flows through the electrode,showing an easy and potential way for multi-functional flow monitoring in microfluidic chips.展开更多
There was limited knowledge about the flow fluctuations and cycling processes of saline springs in the Nangqen Basin in the Sanjiang tectonic zone.In this work,the flow variations of the saline springs during the wet ...There was limited knowledge about the flow fluctuations and cycling processes of saline springs in the Nangqen Basin in the Sanjiang tectonic zone.In this work,the flow variations of the saline springs during the wet and dry seasons were monitored using volumetric and cross-sectional methods,and the cycling process of the saline springs was quantitatively identified using the integrated hydrochemical and isotopic methods.The results show that most saline springs in the Nangqen Basin had significantly different flow rates,ion concentrations,and TDS concentrations.The ions mainly come from carbonate and sulfate minerals.There is no internal hydraulic connection between these saline springs,and the impact of seasonal changes on the flow is relatively small,indicating that the saline springs originate mainly from deep circulation.The recharge elevation of the saline springs ranges 3661-4990 m a.s.l.,with an average of 4100 m a.s.l.The circulation depth of the saline springs ranges of 240-570 m,with an average of 431 m.The recycle time ranges of 1.15-30.86 years,with an average of 15.66 years.These results could provide a scientific basis for the development and utilization of saline spring resources in the Nangqen Basin.展开更多
Computer vision techniques, in conjunction with acquisition through remote cameras and unmanned aerial vehicles (UAVs), offer promising non-contact solutions to civil infrastructure condition assessment. The ultimate ...Computer vision techniques, in conjunction with acquisition through remote cameras and unmanned aerial vehicles (UAVs), offer promising non-contact solutions to civil infrastructure condition assessment. The ultimate goal of such a system is to automatically and robustly convert the image or video data into actionable information. This paper provides an overview of recent advances in computer vision techniques as they apply to the problem of civil infrastructure condition assessment. In particular, relevant research in the fields of computer vision, machine learning, and structural engineering is presented. The work reviewed is classified into two types: inspection applications and monitoring applications. The inspection applications reviewed include identifying context such as structural components, characterizing local and global visible damage, and detecting changes from a reference image. The monitoring applications discussed include static measurement of strain and displacement, as well as dynamic measurement of displacement for modal analysis. Subsequently, some of the key challenges that persist toward the goal of automated vision-based civil infrastructure and monitoring are presented. The paper concludes with ongoing work aimed at addressing some of these stated challenges.展开更多
随着人们对人数统计需求的不断增长,基于信道状态信息(channel state information,CSI)的人流量监测技术因其易于部署、保护隐私和适用性强等优势而备受关注.然而,在现有的人流量监测工作中,人数识别的准确率容易受到人群密集程度的影响...随着人们对人数统计需求的不断增长,基于信道状态信息(channel state information,CSI)的人流量监测技术因其易于部署、保护隐私和适用性强等优势而备受关注.然而,在现有的人流量监测工作中,人数识别的准确率容易受到人群密集程度的影响.为了保证监测精度,通常只能在人群稀疏的情况下进行监测,这导致了基于CSI的人流量监测技术缺乏实用性.为了解决这一问题,提出了一种能够识别连续性人流的监测方法.该方法首先利用解卷绕和线性相位校正算法,对原始数据进行相位补偿并消除随机相位偏移;然后通过标准差和方差提取连续性人流数据中的有效数据包;最后将时域上的相位差信息作为特征信号输入到深度学习的CLDNN(convolutional,long short-term memory,deep neural network)中进行人数识别.经过实验测试,该方法在前后排行人距离不小于1 m的情况下,分别实现了室外96.7%和室内94.1%的准确率,优于现有的人流量监测方法.展开更多
基金Taiwan Soil and Water Conservation Bureau (SWCB- 95-164)
文摘Since 2002, the Soil and Water Conservation Bureau, which is responsible for the conservation and administrative management of hillside in Taiwan, has been cooperating with Feng Chia University. Together, they have successfully carried out the establishment and maintenance of 13 fixed debris flow monitoring stations over the island and 2 mobile debris flow monitoring stations. During July 2004, a powerful southwest air current brought by Mindulle Typhoon caused serious flood in central and southern Taiwan. This paper aims to describe the establishment of debris flow monitoring systems in Taiwan and the observation of the debris flow event during Mindulle Typhoon at Aiyuzi River in Shenmu Village, Nantou County by the monitoring station.
基金This work was supported by the National High-Tech Foundation(863)under the gr ant 2001AA335020.
文摘Liquid composite moulding (LCM) processes are used to manufacture high quality and complex-shaped composite parts in the automotive, marine, aerospace and civil industries. On-line sensing plays an important role in controlling the quality of the final product in the LCM manufacturing environment. The long-period fiber grating (LPG) technology, a new real-time fiber optic sensor system, was developed to monitor the flow front progression. The sensor operation and characterization under various process conditions were discussed in detail. The experimental results showed that LPG sensors were robust and reliable to detect the arrival of resin at pre-selected locations in structures with low-medium fiber volume fraction; however were limited at different depths in structures with high fiber volume fraction.
基金GIST Research Institute(GRI)funded by GIST in 2019 and 2020Brain Research Program(2016M3C7A1905475)+1 种基金Basic Research Program(2018R1A2B6006797)through the National Research Foundation of Korea(NRF)funded by Ministry of Science and ICTKBRI basic research program through Korea Brain Research Institute funded by Ministry of Science and ICT(21-BR-03-05)。
文摘Laser speckle imaging is a common technique to monitor blood flow.The fluctuations in speckle intensity can be related to the blood flow by calculating the speckle contrast,the ratio between the standard deviation of speckle fluctuations and the average intensity.However,this simple statistic calculation is easily affected by motion artifacts.In this study,we applied sample entropy analysis instead of calculating standard deviations of the speckle fluctuations.Similar to the traditional method,sample entropy-based speckle contrast increases linearly with flow rate but was shown to be more immune to sudden movements during an upper arm occlusion test.
基金supported by the National Natural Science Foundation of China(Grant Nos.51976141,52006123,62161160311).
文摘Convenient non-invasive flow monitoring would facilitate the operation and control in microfluidic chips,but is challenging due to the small space of microchannels and complex operation required in traditional optical methods.In this work,we propose a novel non-invasive strategy to probe microfluidic flows via streaming potential phenomenon.By sealing one side of the microchannel with a piece of hydrogel film,streaming potential inside the channel can be clearly detected by electrodes at outer surface of the hydrogel due to ion diffusion in the hydrogel.Flow is detected without sensors contacting with the internal liquid.Moreover,the electrodes shape like a tiny probe,which can move around mapping the flow distribution in a chip with the spatial resolution of 1 mm and flow rate detection limit of 3μL·min–1.Bubbles inside the channels can also be detected,due to the fluctuation of streaming voltage when gas-liquid interface flows through the electrode,showing an easy and potential way for multi-functional flow monitoring in microfluidic chips.
基金supported by the National Natural Science Foundation of China(Nos.42007169,U20A2088)the Natural Science Foundation of Qinghai Province(No.2020-ZJ-932Q)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(No.2019QZKK0805-02)。
文摘There was limited knowledge about the flow fluctuations and cycling processes of saline springs in the Nangqen Basin in the Sanjiang tectonic zone.In this work,the flow variations of the saline springs during the wet and dry seasons were monitored using volumetric and cross-sectional methods,and the cycling process of the saline springs was quantitatively identified using the integrated hydrochemical and isotopic methods.The results show that most saline springs in the Nangqen Basin had significantly different flow rates,ion concentrations,and TDS concentrations.The ions mainly come from carbonate and sulfate minerals.There is no internal hydraulic connection between these saline springs,and the impact of seasonal changes on the flow is relatively small,indicating that the saline springs originate mainly from deep circulation.The recharge elevation of the saline springs ranges 3661-4990 m a.s.l.,with an average of 4100 m a.s.l.The circulation depth of the saline springs ranges of 240-570 m,with an average of 431 m.The recycle time ranges of 1.15-30.86 years,with an average of 15.66 years.These results could provide a scientific basis for the development and utilization of saline spring resources in the Nangqen Basin.
基金supported in part by funding from the US Army Corps of Engineers under a project entitled ‘‘Cybermodeling: A Digital Surrogate Approach for Optimal Risk-Based Operations and Infrastructure” (W912HZ-17-2-0024)
文摘Computer vision techniques, in conjunction with acquisition through remote cameras and unmanned aerial vehicles (UAVs), offer promising non-contact solutions to civil infrastructure condition assessment. The ultimate goal of such a system is to automatically and robustly convert the image or video data into actionable information. This paper provides an overview of recent advances in computer vision techniques as they apply to the problem of civil infrastructure condition assessment. In particular, relevant research in the fields of computer vision, machine learning, and structural engineering is presented. The work reviewed is classified into two types: inspection applications and monitoring applications. The inspection applications reviewed include identifying context such as structural components, characterizing local and global visible damage, and detecting changes from a reference image. The monitoring applications discussed include static measurement of strain and displacement, as well as dynamic measurement of displacement for modal analysis. Subsequently, some of the key challenges that persist toward the goal of automated vision-based civil infrastructure and monitoring are presented. The paper concludes with ongoing work aimed at addressing some of these stated challenges.
