Developing a Google Earth-Based Method to Measure Sight Distance for U-Turns at Unsignalized Intersections on Multilane Divided Highways

Author(s):  
Li Quan ◽  
Beijia Zhang ◽  
Huaguo Zhou ◽  
Pan Liu

The median U-turn is one of the most popular access management techniques implemented by state transportation agencies. Sight distance (SD) is among the key elements for the safe operation of median U-turns. The traditional method of measuring SD is using sight rods in the field, which is inconvenient and unsafe; thus, it is important to develop a convenient and safer method to measure SD for U-turn movement. The objective of this study is to develop a safe and cost-effective method to measure SD for U-turn vehicles, without going into the field, using existing tools in Google Earth and a perspective grid method that can be generated by Kinovea software. The method can be used in two different road geometric conditions: (i) a straight segment with crest curves; (ii) a roadway with a combination of crest curves and horizontal curves. For Condition (i), an empirical equation was developed to estimate SD as a function of distance and elevation along the sight line measured using Google Earth. For Condition (ii), a perspective grid was first applied using Google Earth ground-level view; then the number of broken lines and gaps in each perspective grid cell was used to measure the SD. All inputs can be collected using Google Earth. Field measurements of SD for U-turns at 10 selected locations were conducted to verify the validity of the method. The results show that the differences between the model estimates and field measurements are all less than 10%.

2018 ◽  
Vol 47 (3) ◽  
pp. 417-436 ◽  
Author(s):  
Maria Pafi ◽  
Christos Chalkias ◽  
Demetris Stathakis

In this study, we propose a cost-effective method for tranquillity mapping using multi-criteria analysis and open geospatial data. We apply this method in an extended zone around a major Greek highway trespassing areas of high natural value. Composite criteria are developed through analytic functions and geostatistical methods to reflect either barriers or enablers of tranquillity. The results indicate that it is possible to identify tranquility zones which are spatially plausible. To verify the validity of the results, we calculate the Kappa coefficient (0.71) and the overall accuracy (80%) using preference data obtained from non-specialized photo-interpreters in a sample of places on Google Earth. We believe that this method can inform planning, especially in countries with a weak landscape policy.


2018 ◽  
Author(s):  
Emilio Guirado ◽  
Siham Tabik ◽  
Marga L. Rivas ◽  
Domingo Alcaraz-Segura ◽  
Francisco Herrera

AbstractDespite their interest and threat status, the number of whales in world’s oceans remains highly uncertain. Whales detection is normally carried out from costly sighting surveys, acoustic surveys or through high-resolution orthoimages. Since deep convolutional neural networks (CNNs) achieve great performance in object-recognition in images, here we propose a robust and generalizable CNN-based system for automatically detecting and counting whales from space based on open data and tools. A test of the system on Google Earth images in ten global whale-watching hotspots achieved a performance (F1-measure) of 84% in detecting and 97% in counting 80 whales. Applying this cost-effective method worldwide could facilitate the assessment of whale populations to guide conservation actions. Free and global access to high-resolution imagery for conservation purposes would boost this process.


The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.


1996 ◽  
Vol 33 (8) ◽  
pp. 23-29 ◽  
Author(s):  
I. Dor ◽  
N. Ben-Yosef

About one hundred and fifty wastewater reservoirs store effluents for irrigation in Israel. Effluent qualities differ according to the inflowing wastewater quality, the degree of pretreatment and the operational parameters. Certain aspects of water quality like concentration of organic matter, suspended solids and chlorophyll are significantly correlated with the water column transparency and colour. Accordingly optical images of the reservoirs obtained from the SPOT satellite demonstrate pronounced differences correlated with the water quality. The analysis of satellite multispectral images is based on a theoretical model. The model calculates, using the radiation transfer equation, the volume reflectance of the water body. Satellite images of 99 reservoirs were analyzed in the chromacity space in order to classify them according to water quality. Principal Component Analysis backed by the theoretical model increases the method sensitivity. Further elaboration of this approach will lead to the establishment of a time and cost effective method for the routine monitoring of these hypertrophic wastewater reservoirs.


2013 ◽  
Vol 10 (3) ◽  
pp. 159-163 ◽  
Author(s):  
Jun Peng ◽  
Yue Feng ◽  
Zhu Tao ◽  
Yingjie Chen ◽  
Xiangnan Hu

2001 ◽  
Vol 47 (1) ◽  
pp. 110-117 ◽  
Author(s):  
Magnus Jonsson ◽  
Joyce Carlson ◽  
Jan-Olof Jeppsson ◽  
Per Simonsson

Abstract Background: Electrophoresis of serum samples allows detection of monoclonal gammopathies indicative of multiple myeloma, Waldenström macroglobulinemia, monoclonal gammopathy of undetermined significance, and amyloidosis. Present methods of high-resolution agarose gel electrophoresis (HRAGE) and immunofixation electrophoresis (IFE) are manual and labor-intensive. Capillary zone electrophoresis (CZE) allows rapid automated protein separation and produces digital absorbance data, appropriate as input for a computerized decision support system. Methods: Using the Beckman Paragon CZE 2000 instrument, we analyzed 711 routine clinical samples, including 95 monoclonal components (MCs) and 9 cases of Bence Jones myeloma, in both the CZE and HRAGE systems. Mathematical algorithms developed for the detection of monoclonal immunoglobulins (MCs) in the γ- and β-regions of the electropherogram were tested on the entire material. Additional algorithms evaluating oligoclonality and polyclonal concentrations of immunoglobulins were also tested. Results: CZE electropherograms corresponded well with HRAGE. Only one IgG MC of 1 g/L, visible on HRAGE, was not visible after CZE. Algorithms detected 94 of 95 MCs (98.9%) and 100% of those visible after CZE. Of 607 samples lacking an MC on HRAGE, only 3 were identified by the algorithms (specificity, 99%). Algorithms evaluating total gammaglobulinemia and oligoclonality also identified several cases of Bence Jones myeloma. Conclusions: The use of capillary electrophoresis provides a modern, rapid, and cost-effective method of analyzing serum proteins. The additional option of computerized decision support, which provides rapid and standardized interpretations, should increase the clinical availability and usefulness of protein analyses in the future.


Author(s):  
Trine S. Mykkeltvedt ◽  
Sarah E. Gasda ◽  
Tor Harald Sandve

AbstractCarbon-neutral oil production is one way to improve the sustainability of petroleum resources. The emissions from produced hydrocarbons can be offset by injecting capture CO$$_{2}$$ 2 from a nearby point source into a saline aquifer for storage or a producing oil reservoir. The latter is referred to as enhanced oil recovery (EOR) and would enhance the economic viability of CO$$_{2}$$ 2 sequestration. The injected CO$$_{2}$$ 2 will interact with the oil and cause it to flow more freely within the reservoir. Consequently, the overall recovery of oil from the reservoir will increase. This enhanced oil recovery (EOR) technique is perceived as the most cost-effective method for disposing captured CO$$_{2}$$ 2 emissions and has been performed for many decades with the focus on oil recovery. The interaction between existing oil and injected CO$$_{2}$$ 2 needs to be fully understood to effectively manage CO$$_{2}$$ 2 migration and storage efficiency. When CO$$_{2}$$ 2 and oil mix in a fully miscible setting, the density can change non-linearly and cause density instabilities. These instabilities involve complex convective-diffusive processes, which are hard to model and simulate. The interactions occur at the sub-centimeter scale, and it is important to understand its implications for the field scale migration of CO$$_{2}$$ 2 and oil. In this work, we simulate gravity effects, namely gravity override and convective mixing, during miscible displacement of CO$$_{2}$$ 2 and oil. The flow behavior due to the competition between viscous and gravity effects is complex, and can only be accurately simulated with a very fine grid. We demonstrate that convection occurs rapidly, and has a strong effect on breakthrough of CO$$_{2}$$ 2 at the outlet. This work for the first time quantifies these effects for a simple system under realistic conditions.


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