scholarly journals Monitoring System for Circular Deformation in Metro Shield Tunnels in Soft Soils

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Jinfeng Zhang ◽  
Ming Zhao
Keyword(s):  
Rigid Body ◽  
Cost Effective ◽  
Automatic Monitoring ◽  
Transportation Safety ◽  
Shield Tunnel ◽  
Opening Angle ◽  
Monitoring Methods ◽  
Joint Rotation ◽  
Soft Soils ◽  
Joint Opening

For in-service metro shield tunnels in soft soils, large circular deformations are a major concern because they usually lead to various problems, such as water leakage, joint openings, and concrete cracks. However, the monitoring of circular deformation depends mainly on manual surveying, and the automatic monitoring methods developed in recent years generally have low economic applicability and are not widely implemented. In this study, an automatic and cost-effective system was presented to monitor circular deformation in shield tunnels by using only inclinometers. Experiments were conducted to prove the assumption that each segment can be regarded as a rigid body and to investigate the position of the joint rotation center. Then, a method for monitoring circular deformation based on the rigid body and plane section assumptions was proposed. The joint opening angle, maximum joint opening width, horizontal diameter convergence, and bolt strain were calculated from rotation angles of segments which can be monitored directly by inclinometer. A case study was conducted for a section of a metro shield tunnel with an ongoing pit excavation nearby. The rotation of segments was measured using MEMS inclinometers, and the data were transmitted using ZigBee and general packet radio service (GPRS) wireless communication technology. Results show that the proposed system could be implemented to improve transportation safety in relevant situations and similar conditions.

scholarly journals An Automated Light Trap to Monitor Moths (Lepidoptera) Using Computer Vision-Based Tracking and Deep Learning

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 343
Author(s):  
Kim Bjerge ◽  
Jakob Bonde Nielsen ◽  
Martin Videbæk Sepstrup ◽  
Flemming Helsing-Nielsen ◽  
Toke Thomas Høye
Keyword(s):  
Computer Vision ◽  
Deep Learning ◽  
Vision System ◽  
Low Cost ◽  
Light Trap ◽  
Automatic Monitoring ◽  
Light Sources ◽  
Monitoring Methods ◽  
Computer Vision System ◽  
Substantial Investment

Insect monitoring methods are typically very time-consuming and involve substantial investment in species identification following manual trapping in the field. Insect traps are often only serviced weekly, resulting in low temporal resolution of the monitoring data, which hampers the ecological interpretation. This paper presents a portable computer vision system capable of attracting and detecting live insects. More specifically, the paper proposes detection and classification of species by recording images of live individuals attracted to a light trap. An Automated Moth Trap (AMT) with multiple light sources and a camera was designed to attract and monitor live insects during twilight and night hours. A computer vision algorithm referred to as Moth Classification and Counting (MCC), based on deep learning analysis of the captured images, tracked and counted the number of insects and identified moth species. Observations over 48 nights resulted in the capture of more than 250,000 images with an average of 5675 images per night. A customized convolutional neural network was trained on 2000 labeled images of live moths represented by eight different classes, achieving a high validation F1-score of 0.93. The algorithm measured an average classification and tracking F1-score of 0.71 and a tracking detection rate of 0.79. Overall, the proposed computer vision system and algorithm showed promising results as a low-cost solution for non-destructive and automatic monitoring of moths.

Differential settlement remediation for new shield metro tunnel in soft soils using corrective grouting method: case study

2018 ◽  
Vol 55 (12) ◽  
pp. 1877-1887 ◽  
Author(s):  
Shunhua Zhou ◽  
Junhua Xiao ◽  
Honggui Di ◽  
Yaohong Zhu
Keyword(s):  
Yangtze River Delta ◽  
Differential Settlement ◽  
Shield Tunnel ◽  
Soft Soils ◽  
Average Value ◽  
Acceptable Deviation ◽  
Metro Tunnel ◽  
The Yangtze River Delta ◽  
Metro System

In the Yangtze River Delta of China, a large number of metro tunnels have been constructed in soft soils. The excessive and differential tunnel settlement may impair the serviceability of the metro system. The treatment of such excessive and differential settlement in rheologic and sensitive soft soils is a challenge because the tunnel may incur a larger settlement due to construction disturbances. In this paper, a case study of the differential settlement treatment of the new shield tunnel of Ningbo Metro line 2 is presented. A maximum tunnel settlement of 214 mm was observed several months after construction of the tunnel was completed. To uplift the deviated tunnel axis, a grouting and lifting measure named “bottom grouting, inner support, real-time monitoring and immediate adjusting” is proposed. The settlement treatment section is successfully uplifted with an average value of 30 mm, and the maximum final uplift amount of the tunnel is 41 mm, which reached the target value of uplift. The maximum convergence deformation caused by the grouting is 10 mm, which is less than the maximum acceptable deviation, i.e., 15.5 mm. The corrective grouting method and the valuable monitoring data presented in this study can provide a reference for projects with similar problems in the future.

Substructure Flexibility and Member-Level Load Capabilities for Floating Offshore Wind Turbines in OpenFAST

2019 ◽  
Author(s):  
Jason M. Jonkman ◽  
Rick R. Damiani ◽  
Emmanuel S. P. Branlard ◽  
Matthew Hall ◽  
Amy N. Robertson ◽  
...  
Keyword(s):  
Rigid Body ◽  
Wind Turbines ◽  
Cost Effective ◽  
Offshore Wind ◽  
Functional Requirements ◽  
Global Response ◽  
Offshore Wind Turbines ◽  
Floating Offshore Wind Turbines ◽  
Load Analysis ◽  
Source Physics

Abstract OpenFAST is an open-source, physics-based engineering tool applicable to the load analysis of land-based and offshore wind turbines, including floating offshore wind turbines. The substructure for a floating wind turbine has historically been modeled in OpenFAST as a rigid body with hydrodynamic loads lumped at a point, which enabled the tool to predict the global response of the floating substructure but not the structural loads within its individual members. This limitation is an impediment to designing floating substructures — especially newer designs that are more streamlined, flexible, and cost-effective. This paper presents the development plan of new capabilities in OpenFAST to model floating substructure flexibility and member-level loads, including the functional requirements and modeling approaches needed to understand and apply them correctly.

Theoretical Study on Establishing Hydro-Eco Dynamic Monitoring System in Large-Scale and Arid Irrigation District

2013 ◽  
Vol 726-731 ◽  
pp. 3787-3791
Author(s):  
Zhi Feng Jia ◽  
Wen Bin Li
Keyword(s):  
Monitoring System ◽  
Large Scale ◽  
Water Cycle ◽  
Automatic Monitoring ◽  
Water Shortage ◽  
Irrigation District ◽  
Dynamic Monitoring ◽  
Satellite Monitoring ◽  
Monitoring Methods ◽  
Meteorological Elements

As for some large-scale and arid irrigation district in China, such as Jinghuiqu irrigation district and Shihezi reclamation district, hydro-ecosystem was gradually degenerated and imbalanced due to water shortage and unreasonable exploitation. In order to study hydrological elements, water cycle process and ecological response caused by human activities and other factors, and improve the quality of hydro-ecosystem, scientific connotation of establishing hydro-eco dynamic monitoring system in large-scale and arid irrigation district was defined. Hydro-ecosystem dynamic monitoring indexes including meteorological elements, hydrological elements, ecological elements closely related to hydrological elements and cycle, and socio-economic elements were proposed. Comprehensive monitoring methods based on automatic monitoring net, remote sensing satellite monitoring, field test and investigation were determined, and overall framework of hydro-eco dynamic monitoring was designed, which provided a theoretical basis for establishing hydro-eco dynamic monitoring system in large-scale and arid irrigation district.

Comparison of the Effect of Soil Treatment Methods Used in Highway Widening Projects

2013 ◽  
Vol 663 ◽  
pp. 3-7
Author(s):  
Min Zhao ◽  
Wei Ping Cao ◽  
Qi Chao Shi
Keyword(s):  
Rapid Development ◽  
Heavy Traffic ◽  
Soft Soil ◽  
Cost Effective ◽  
Stone Columns ◽  
Engineering Practice ◽  
Soft Soils ◽  
Prefabricated Vertical Drains ◽  
Vertical Drains ◽  
Effective Choice

The rapid development of China’s economics makes it urgent to widen the existing highways especially those located in the south-eastern coastal areas over thick soft soils. Adding a new embankment adjacent to the existing highway embankment is a cost effective choice compared with the traditional methods to build another new one and can reduce the heavy traffic pressure. However, it may also cause some engineering problems including the excessive settlements settlements, road cracks, excessive tensile stresses on the pavement even local or global instability of embankments. So some proper measures should be taken to solve the problems caused by widening is of great importance in engineering practice. A numerical analysis was performed to investigate the effect of different kinds of soft soil treatments including rigid piles, stone columns and prefabricated vertical drains (PVDs) usually used in highway widening projects located in the thick soft soils. It was found that the rigid piles can effectively reduce the additional settlements of the existing embankment induced by widening as well as the settlements of the widened embankment. While the stone columns and PVDs play little role in controlling the additional settlements caused by widening.

scholarly journals The dynamics of invasive and noninvasive blood glucose monitoring methods: Recent trends

2016 ◽  
Vol 19 (5) ◽  
pp. 397-405 ◽  
Author(s):  
Alina Yur'evna Babenko ◽  
Yulia Alexeevna Kononova ◽  
Alexandr Ivanovich Tsiberkin ◽  
Michail Konstantinovich Khodzitsky ◽  
Elena Nilkolaevna Grineva
Keyword(s):  
Blood Glucose ◽  
Blood Glucose Control ◽  
Glucose Monitoring ◽  
Cost Effective ◽  
Disease Status ◽  
Accurate Method ◽  
Blood Glucose Monitoring ◽  
Monitoring Methods ◽  
Glucose Levels ◽  
Blood Glucose Levels

Improved prognoses of patients with type 2 diabetes are primarily determined by the extent of blood glucose control (correction of both hyper- and hypoglycemia and normalization of blood glucose levels). The proper identification and timely correction of abnormal blood glucose levels require frequent blood glucose monitoring by the patient. Currently used methods for the self-monitoring of blood glucose have significant drawbacks that limit their use. The most significant problems with these methods include insufficient accuracy, invasiveness and high cost, leading to noncompliance and difficult assessment of disease status. Such factors underscore the need for a noninvasive, cost-effective and highly accurate method to measure blood glucose levels. There are several different approaches for the noninvasive measurement of blood glucose levels, including optical analysis, ultrasound and bioimpedance. The concept of a noninvasive glucometer was launched more than 30 years ago. Nevertheless, most noninvasive technologies are still in early stages of development and are not used in clinical practice. This review describers the most promising developments in this area.

scholarly journals Technological developments as an answer to bridge management challenges

2019 ◽  
Author(s):  
Andre Orcesi ◽  
Bruno Godart ◽  
Laurent Gaillet ◽  
Franziska Schmidt ◽  
Nicolas Bardou ◽  
...  
Keyword(s):  
Cost Effective ◽  
Bridge Management ◽  
Monitoring Methods ◽  
High Expectations ◽  
Bridge Monitoring ◽  
Technological Developments ◽  
Integrated Cost ◽  
And Performance ◽  
And Shifts ◽  
Non Destructive

<p>Bridge management is a challenge as owners have to deal with limited financial resources to maintain the functionalities and safety of ageing structures. Demands on transportation networks change, due to regulatory developments, society's evolution and shifts with high expectations on the operational performance of roadway bridges with reduced congestion, delay, and accidents. To minimize intrusion in the transport flow, inspection and monitoring methods should be non-destructive, minimally invasive. They should be capable of yielding rapid and accurate inspection results allowing an adequate response from the asset manager. Research aims at including autonomously operating equipment (e.g. robotics), non-intrusive (remote or proximity) observation techniques, or other methods that ensure quality and performance control of the roadway bridges in time, more safely, more quickly and/or to a higher degree of accuracy and precision.The innovation subgroup in COST action TU1406 investigates novel condition monitoring and sensing technologies for the assessment of structural serviceability and safety. Advanced, integrated, cost-effective and reliable instrumentation solutions, techniques and concepts are looked at with the aim to provide data, that will be used to compute innovative performance indicators. In this context, this paper briefly reminds some significant challenges associated with bridge management and presents three examples of innovation in bridge monitoring and NDT investigation techniques.</p>

scholarly journals Learning to count: adapting population monitoring for Endangered huemul deer Hippocamelus bisulcus to meet conservation objectives

2020 ◽  
Author(s):  
Heiko Wittmer ◽  
P Corti ◽  
C Saucedo ◽  
J Galaz
Keyword(s):  
Survey Data ◽  
Survey Methods ◽  
Cost Effective ◽  
Population Monitoring ◽  
Population Trends ◽  
Monitoring Methods ◽  
Monitoring Method ◽  
Hippocamelus Bisulcus ◽  
Detection Probabilities ◽  
Current Survey

Considerable efforts have been invested in recent years to improve methods for both data collection and analyses required for population monitoring. Where historical or current estimates of population size are not adjusted for detection probabilities they may be too inaccurate to provide meaningful estimates of trends and thus monitoring methods need to be adapted. Here, we use data from the Endangered huemul deer Hippocamelus bisulcus to outline a framework to develop accurate robust estimates of detection probabilities that can be incorporated into new surveys in a cost-effective way and applied to existing survey data sets. In particular, by retroactively estimating detection probabilities for surveys of huemul, we show that current survey methods for huemul are inadequate to determine population trends reliably. Based on these results we propose a new monitoring method for the huemul and discuss the importance of estimating accuracies of historical survey data to ensure that changes in the abundance of the species reflect real population trends and are not an artefact of variation over time in the accuracy of survey data. © 2010 Fauna & Flora International.

scholarly journals Learning to count: adapting population monitoring for Endangered huemul deer Hippocamelus bisulcus to meet conservation objectives

2020 ◽  
Author(s):  
Heiko Wittmer ◽  
P Corti ◽  
C Saucedo ◽  
J Galaz
Keyword(s):  
Survey Data ◽  
Survey Methods ◽  
Cost Effective ◽  
Population Monitoring ◽  
Population Trends ◽  
Monitoring Methods ◽  
Monitoring Method ◽  
Hippocamelus Bisulcus ◽  
Detection Probabilities ◽  
Current Survey

Considerable efforts have been invested in recent years to improve methods for both data collection and analyses required for population monitoring. Where historical or current estimates of population size are not adjusted for detection probabilities they may be too inaccurate to provide meaningful estimates of trends and thus monitoring methods need to be adapted. Here, we use data from the Endangered huemul deer Hippocamelus bisulcus to outline a framework to develop accurate robust estimates of detection probabilities that can be incorporated into new surveys in a cost-effective way and applied to existing survey data sets. In particular, by retroactively estimating detection probabilities for surveys of huemul, we show that current survey methods for huemul are inadequate to determine population trends reliably. Based on these results we propose a new monitoring method for the huemul and discuss the importance of estimating accuracies of historical survey data to ensure that changes in the abundance of the species reflect real population trends and are not an artefact of variation over time in the accuracy of survey data. © 2010 Fauna & Flora International.

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