Measurement Techniques of Precasting the No.4 Nanjing Yangtze River Bridge’s Segmental Girders by Short-Line

2011 ◽  
Vol 90-93 ◽  
pp. 2891-2896
Author(s):  
Ling Liu ◽  
Teng Huang ◽  
Xi Feng Chen
Keyword(s):  
Error Correction ◽  
Yangtze River ◽  
Measurement Techniques ◽  
Deformation Monitoring ◽  
Concrete Bridges ◽  
Control Network ◽  
Construction Control ◽  
Short Line ◽  
Control Techniques ◽  
The Way

Based on the example of the No.4 Nanjing Yangtze River Bridge, the construction technics of precasting segmental girders by short-line is introduced. And the way of plant deformation monitoring as well as the establishment of horizontal and vertical construction control network in the precast plant are expatiated on. In addition, the measurement techniques during the installation of the fixed-mold, unfixed-mold, lineshape control techniques of the segmental girders, as well as the error correction theories during precasting process are discussed in particular. The short-line is successfully applied to the No.4 Nanjing Yangtze River Bridge, which shows its practical value in precasting segmental concrete bridges.

Accuracy of Static Differential GPS Techniques; Implications for Structural Deformation Monitoring

2009 ◽  
Vol 62-64 ◽  
pp. 31-38
Author(s):  
J.O. Ehiorobo
Keyword(s):  
Carrier Phase ◽  
Reference Frames ◽  
Phase Measurement ◽  
Sampling Rate ◽  
Tall Buildings ◽  
Deformation Monitoring ◽  
Structural Deformation ◽  
Control Network ◽  
Differential Gps ◽  
Engineering Structures

In recent years, the need to monitor for Deformation in Engineering Structures such as Dams, Bridges and Tall buildings have become more necessary as a result of reported failures of many of these structures with catastrophic consequences globally. Global Positioning System (GPS) is highly automated and less labour intensive than other conventional techniques used in structural deformation monitoring. For most applications, such as National Geodetic Control Network, Urban Control Network and other Engineering Control Network, an accuracy in the cm level for most GPS work is quite adequate. For Structural deformation monitoring however, the required accuracy is in millimeters. In this paper, the use of Static Differential GPS method with multiple receivers for high precision measurement was investigated using the monitoring Stations at Ikpoba Dam as case study Scenerio. Four units of LEICA 300 Dual Frequency GPS receivers were deployed for code and carrier phase measurements with observation session of 1hr at a sampling rate of 15 sec. Baseline Processing and Least Squares Adjustment of observation was carried out in WGS 84 and NTM reference frames using the LEICA SKI-PRO Processing software and Move. Analysis of the results revealed that the number of outliers in the observation were <5% and the accuracy of horizontal and vertical coordinates were 4mm maximum for horizontal and 2mm maximum for vertical. The study revealed that in areas with favourable satellite constellation and appropriate reduction or elimination of multipath and other noise like errors, Static Differential GPS techniques with a combination of code and carrier phase measurement gives good results for structural deformation monitoring.

scholarly journals Contribuciones teóricas sobre la metodología colaborativa para el tratamiento de los errores gramaticales de un texto académico en inglés en un contexto universitario

2017 ◽  
Vol 21 (2) ◽  
pp. 1
Author(s):  
Mabel Andrea Ortiz-Navarrete ◽  
Claudio Heraldo Diaz-Larenas
Keyword(s):  
Error Correction ◽  
Collaborative Work ◽  
Corrective Feedback ◽  
Zone Of Proximal Development ◽  
Active Participation ◽  
Proximal Development ◽  
Positive Interdependence ◽  
Collaborative Methodology ◽  
The Way

This article aims to highlight the characteristics of the collaborative methodology for error correction of L2 students’ texts. The article points out the following components: interaction, dialogue, discussion, scaffolding, ZPD (Zone of proximal development), and positive interdependence; these components also favor the active participation of all members of a group during error correction. In addition, the paper emphasizes the way the collaborative work can activate the metalinguistic component, and can enhance the effect of corrective feedback provided by the teacher to a group.

Monitoring permafrost changes in the Yangtze River source region of the Qinghai-Tibetan Plateau using differential SAR interferometry

2020 ◽  
Author(s):  
Lingxiao Wang ◽  
Lin Zhao ◽  
Huayun Zhou ◽  
Shibo Liu ◽  
Xiaodong Huang ◽  
...  
Keyword(s):  
Active Layer ◽  
Yangtze River ◽  
Ground Deformation ◽  
Source Region ◽  
Deformation Monitoring ◽  
Tibet Plateau ◽  
Permafrost Degradation ◽  
The Yangtze River ◽  
Ground Ice

&lt;p&gt;Qinghai-Tibet Plateau (QTP) has the largest high-altitude permafrost zone in the middle and low latitudes. Substantial hydrologic changes have been observed in the Yangtze River source region and adjacent areas in the early 21st century. Permafrost on the QTP has undergone degradation under global warming. The ground leveling observation site near Tangula (33&amp;#176;04&amp;#8242;N, 91&amp;#176;56&amp;#8242;E) located in the degraded alpine meadow indicates that the ground has subsided 50mm since 2011. The contribution of permafrost degradation and loss of ground ice to the hydrologic changes is however still lacking. This study monitors the permafrost changes by applying the Small BAseline Subset InSAR (SBAS-InSAR) technique using C-band Sentinel-1 datasets during 2014-2019. The ground deformation over permafrost terrain is derived in spatial and temporal scale, which reflects the seasonal freeze-thaw cycle in the active layer and long-term thawing of ground ice beneath the active layer. Results show the seasonal thaw displacement exhibits a strong correlation with surficial geology contacts. The ground leveling data is used to validate the ground deformation monitoring results. Then, the ground deformation characteristics are analyzed against the landscape units. Last, the long-term inter-annual displacement value is used to estimate the water equivalent of ground ice melting.&lt;/p&gt;

scholarly journals How Can EFL Students Be Corrected Without Hindering Oral Participation?

LETRAS ◽  
2007 ◽  
pp. 105-130
Author(s):  
Jimmy Ramírez Acosta
Keyword(s):  
Error Correction ◽  
Oral Participation ◽  
Efl Students ◽  
The Way

 Se describen las técnicas que suelen emplearse para corregir la producción oral de estudiantes de segundas lenguas. Según la forma en que los estudiantes son corregidos, así su deseo de participar. Parte de la información proporcionada se fundamenta en una investigación llevada a cabo con un grupo de estudiantes de inglés en cuanto a sus ideas sobre modelos de corrección y sus propuestas.The error correction techniques commonly applied by teachers to improve students' oral output are described here. The way students' output is treated plays an important role in their desire to participate. Part of the information provided is based on research carried out with a group of students of English conceming their ideas about error correction and the techniques that they proposed.

Technical Issues Related to IT Governance Tactics

2011 ◽  
pp. 216-245
Author(s):  
Michalis Xenos
Keyword(s):  
Decision Making ◽  
Process Control ◽  
Development Process ◽  
Measurement Techniques ◽  
It Governance ◽  
Testing Time ◽  
Effort Estimation ◽  
Statistical Process ◽  
Product Metrics ◽  
Control Techniques

This chapter deals with some technical aspects of the strategies for IT Governance described in most of the other chapters of this book. The practical application of IT Governance techniques and tactics requires the collection and analysis of measurable data that guide estimation, decision-making and assessment, since it is common sense that one can control and manage better what one is able to measure. This chapter aims at introducing the reader to product metrics and measurements, proposing methods relating to the implementation of a measurements program and analyzing how product metrics can be used to control IT development. Focus is placed on product metrics, measurements and process control techniques. Such instruments can aid significantly in monitoring the development process and making IT-related tasks more transparent to IT managers. They also aid in design, prediction and assessment of the IT product quality. They provide data used for decision-making, cost and effort estimation, fault prevention, and testing time reduction. Moreover, the use of product metrics and process control techniques can direct the standardization of IT products and IT development process, as well as the assessment of the process maturity of outsourcing partners. The most commonly used metrics are presented and the reader is introduced to measurement techniques and automation tools. This chapter also discusses the application of metrics along with statistical process control tools. Finally, it provides suggestions on how product metrics can aid towards IT Governance not only in large IT companies, but also in the smaller ones.

Improve the design process of pile foundations using construction control techniques

2019 ◽  
Vol 14 (6) ◽  
pp. 636-643
Author(s):  
Seyed Ali Asghari Pari ◽  
Ghassem Habibagahi ◽  
Arsalan Ghahramani ◽  
Kazem Fakharian
Keyword(s):  
Design Process ◽  
Pile Foundations ◽  
Construction Control ◽  
Control Techniques
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