The Application of Digital Photography Techniques in Structure Deformation Measurement

2013 ◽  
Vol 475-476 ◽  
pp. 204-208 ◽  
Author(s):  
Cheng Xin Yu ◽  
Xiang Xia ◽  
Feng Hua Qin ◽  
Peng Xiao

Introduced the use of 3D time baseline parallax method of steel structure,calculation of deformation measurement data processing methods, and the experimental results are given. This method considered the resolution, focal length, and the impact of external environmental conditions. Has made the small observation error, high precision results.Digital cameras used for digital photographic survey, avoid the complex process of measuring cameras printing. The photographic measurements can be performed simultaneously inside and outside the industry.So far, more suitable for digital camera solver methods are direct linear transformation and time baseline parallax method. Among them, 3D time baseline parallax method is mainly used for measuring spatial displacement of objects.

2017 ◽  
Vol 66 (3) ◽  
pp. 27-44
Author(s):  
Michalina Wojtkowska ◽  
Romuald Kaczyński

Archaeological data are usually inherently incomplete, heterogeneous, discontinuous and require frequent updates and possible adjustments. It is important to constantly create detailed documentation, which will precisely represent the actual situation. However, even the most precise figure is only an estimated representation of the documented object. Therefore, it is necessary to collect fully metric documentation and its professional archaeological interpretation. Acquiring correct and valuable underwaterdigital images for the archaeology purposes is not easy due to specific shooting conditions. It should be noted a number of limitations are unique to this type of imaging environment — the apparent extension of the focal length, the “disappearance” of colours, as well as a significant reduction in the transparency of the water environment. Therefore, the authors have made attempts to describe changes, in a much broader sense, in the quality of photogrammetric images that had been taken in various shooting conditions. Underwater and aerial images of two test fields were tested. First, the ground sampling distance of the INTOVA IC500 digital camera and the geometric accuracy of the acquired images were examined. Then, the impact of changes to the imaging conditions on the radio-metric resolution and colour projection were designated. In the last stage, the acquired images were used in practice — to assess the progress of the erosion process of an archaeological object, and also to comply its documentation in the form of vector drawing with the accuracy of mxy = ±0.5 mm. Keywords: photogrammetry and remote sensing, archaeology, underwater photogrammetry, resolution, ground resolved distance


Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 190
Author(s):  
William Hicks ◽  
Sean Beevers ◽  
Anja H. Tremper ◽  
Gregor Stewart ◽  
Max Priestman ◽  
...  

This research quantifies current sources of non-exhaust particulate matter traffic emissions in London using simultaneous, highly time-resolved, atmospheric particulate matter mass and chemical composition measurements. The measurement campaign ran at Marylebone Road (roadside) and Honor Oak Park (background) urban monitoring sites over a 12-month period between 1 September 2019 and 31 August 2020. The measurement data were used to determine the traffic increment (roadside–background) and covered a range of meteorological conditions, seasons, and driving styles, as well as the influence of the COVID-19 “lockdown” on non-exhaust concentrations. Non-exhaust particulate matter (PM)10 concentrations were calculated using chemical tracer scaling factors for brake wear (barium), tyre wear (zinc), and resuspension (silicon) and as average vehicle fleet non-exhaust emission factors, using a CO2 “dilution approach”. The effect of lockdown, which saw a 32% reduction in traffic volume and a 15% increase in average speed on Marylebone Road, resulted in lower PM10 and PM2.5 traffic increments and brake wear concentrations but similar tyre and resuspension concentrations, confirming that factors that determine non-exhaust emissions are complex. Brake wear was found to be the highest average non-exhaust emission source. In addition, results indicate that non-exhaust emission factors were dependent upon speed and road surface wetness conditions. Further statistical analysis incorporating a wider variability in vehicle mix, speeds, and meteorological conditions, as well as advanced source apportionment of the PM measurement data, were undertaken to enhance our understanding of these important vehicle sources.


2016 ◽  
Vol 142 (697) ◽  
pp. 1767-1780 ◽  
Author(s):  
Niels Bormann ◽  
Massimo Bonavita ◽  
Rossana Dragani ◽  
Reima Eresmaa ◽  
Marco Matricardi ◽  
...  

2021 ◽  
Vol 13 (3) ◽  
pp. 426
Author(s):  
Zheng Qi Wang ◽  
Roger Randriamampianina

The assimilation of microwave and infrared (IR) radiance satellite observations within numerical weather prediction (NWP) models have been an important component in the effort of improving the accuracy of analysis and forecast. Such capabilities were implemented during the development of the high-resolution Copernicus European Regional Reanalysis (CERRA), funded by the Copernicus Climate Change Services (C3S). The CERRA system couples the deterministic system with the ensemble data assimilation to provide periodic updates of the background error covariance matrix. Several key factors for the assimilation of radiances were investigated, including appropriate use of variational bias correction (VARBC), surface-sensitive AMSU-A observations and observation error correlation. Twenty-one-day impact studies during the summer and winter seasons were conducted. Generally, the assimilation of radiances has a small impact on the analysis, while greater impacts are observed on short-range (12 and 24-h) forecasts with an error reduction of 1–2% for the mid and high troposphere. Although, the current configuration provided less accurate forecasts from 09 and 18 UTC analysis times. With the increased thinning distances and the rejection of IASI observation over land, the errors in the analyses and 3 h forecasts on geopotential height were reduced up to 2%.


2018 ◽  
Vol 146 (2) ◽  
pp. 447-465 ◽  
Author(s):  
Mark Buehner ◽  
Ping Du ◽  
Joël Bédard

Abstract Two types of approaches are commonly used for estimating the impact of arbitrary subsets of observations on short-range forecast error. The first was developed for variational data assimilation systems and requires the adjoint of the forecast model. Comparable approaches were developed for use with the ensemble Kalman filter and rely on ensembles of forecasts. In this study, a new approach for computing observation impact is proposed for ensemble–variational data assimilation (EnVar). Like standard adjoint approaches, the adjoint of the data assimilation procedure is implemented through the iterative minimization of a modified cost function. However, like ensemble approaches, the adjoint of the forecast step is obtained by using an ensemble of forecasts. Numerical experiments were performed to compare the new approach with the standard adjoint approach in the context of operational deterministic NWP. Generally similar results are obtained with both approaches, especially when the new approach uses covariance localization that is horizontally advected between analysis and forecast times. However, large differences in estimated impacts are obtained for some surface observations. Vertical propagation of the observation impact is noticeably restricted with the new approach because of vertical covariance localization. The new approach is used to evaluate changes in observation impact as a result of the use of interchannel observation error correlations for radiance observations. The estimated observation impact in similarly configured global and regional prediction systems is also compared. Overall, the new approach should provide useful estimates of observation impact for data assimilation systems based on EnVar when an adjoint model is not available.


2013 ◽  
Vol 14 (4) ◽  
pp. 301-306 ◽  
Author(s):  
Anna Fortoul Obermöller

The Case Study section of the International Journal of Entrepreneurship and Innovation serves two purposes. First, the case studies presented are concerned with problematical issues that are pertinent to students of entrepreneurship. Thus they constitute appropriate teaching and learning vehicles on a variety of postgraduate and undergraduate programmes. Each case study is accompanied by a set of guidelines for the use of tutors. Second, it is envisaged that those engaged in entrepreneurial activities will find the cases both interesting and useful. The case of PSA Peugeot Citroën's electric passenger car is an example of an innovation perceived as a failure because of its disappointing sales volume. Yet, by limiting our assessment of the electric passenger car to a short-term perspective, we may miss out on an essential part of its value. As part of a wider innovation process, the electric passenger car project is a significant step for PSA in its expertise regarding electric vehicles. Key learning outcomes: (a) to understand that innovation is a complex process with fuzzy frontiers, both in time and space; (b) to understand that innovation is a long-term investment with spillovers into other projects; (c) to be aware of the multiple perspectives that may be adopted when examining innovation; and (d) to be aware of the impact of labelling a project a failure.


Energies ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 2442 ◽  
Author(s):  
Jussi Ekström ◽  
Matti Koivisto ◽  
Ilkka Mellin ◽  
Robert Millar ◽  
Matti Lehtonen

In future power systems, a large share of the energy will be generated with wind power plants (WPPs) and other renewable energy sources. With the increasing wind power penetration, the variability of the net generation in the system increases. Consequently, it is imperative to be able to assess and model the behavior of the WPP generation in detail. This paper presents an improved methodology for the detailed statistical modeling of wind power generation from multiple new WPPs without measurement data. A vector autoregressive based methodology, which can be applied to long-term Monte Carlo simulations of existing and new WPPs, is proposed. The proposed model improves the performance of the existing methodology and can more accurately analyze the temporal correlation structure of aggregated wind generation at the system level. This enables the model to assess the impact of new WPPs on the wind power ramp rates in a power system. To evaluate the performance of the proposed methodology, it is verified against hourly wind speed measurements from six locations in Finland and the aggregated wind power generation from Finland in 2015. Furthermore, a case study analyzing the impact of the geographical distribution of WPPs on wind power ramps is included.


2017 ◽  
Author(s):  
Huiting Mao ◽  
Dolly Hall ◽  
Zhuyun Ye ◽  
Ying Zhou ◽  
Dirk Felton ◽  
...  

Abstract. The impact of large-scale circulation on urban gaseous elemental mercury (GEM) was investigated through analysis of 2008–2015 measurement data from an urban site in New York City (NYC), New York, USA. Distinct annual cycles were observed in 2009–2010 with mixing ratios in warm seasons (i.e. spring–summer) 10–20 ppqv (~ 10 %–25 %) higher than in cool seasons (i.e. fall–winter). This annual cycle was disrupted in 2011 by an anomalously strong influence of the North American trough in that warm season and was reproduced in 2014 with annual amplitude enhanced up to ~ 70 ppqv associated with a particularly strong Bermuda High. North American trough axis index (TAI) and intensity index (TII) were used to characterize the effect of the North American trough on NYC GEM especially in winter and summer. The intensity and position of the Bermuda High had a significant impact on GEM in warm seasons supported by a strong correlation (r reaching 0.96, p 


Author(s):  
X. W. Zhang ◽  
T. X. Yu

AbstractBy means of ping-pong balls, the dynamic buckling behaviours of thin-walled spherical shells under impact loading are studied both experimentally and numerically. First, the quasi-static tests were conducted on an MTS tester, in which the ball was compressed onto a PMMA plate. Apart from the force-displacement relationship, the evolution of the contact zone between the ball and the plate was obtained by a digital camera. In the impact tests, ping-pong balls were accelerated by an air-gun and then impinged onto a rigid plate with the velocity ranging 10–45 m


2013 ◽  
Vol 671-674 ◽  
pp. 496-499 ◽  
Author(s):  
Ming Yang Wang ◽  
Yun Peng Chu ◽  
Yong Yao ◽  
Yu Ping Zhu

China is a developing country, and also a quake-prone country. On the one hand is the Special national conditions that per capita energy shortage and frequent earthquakes, on the other hand is the social economy development and people's living environment requirements continue to increase, both of them raised new requirement of China’s residence system development. Light steel structure residence is energy conservation , environmental protection, safety and seismic, these unique advantages just to meet the current development of residential industry in China, so it has a good development prospect. This article start from the realistic background, around the application and development of our country’s light steel structure residence presently, mainly introduced the characteristics of light steel structure residence, the impact of construction industry, and the social benefits, environmental benefits, housing industrialization effective and comprehensive benefits it can produce.


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