scholarly journals Application of digital image processing in slope surface runoff velocity analysis under simulated rainfall conditions

2017 ◽  
Vol 49 (4) ◽  
pp. 1304-1312
Author(s):  
Tiexiong Gong ◽  
Yuanjun Zhu

Abstract To have accurate runoff velocity, there is need to improve dye tracer method for estimating surface runoff velocity. This can enhance the calculations of relevant hydrologic parameters that will lead to a better understanding of hydrological processes and soil erosion. In this study, an integrated dye tracer and image processing method (IPV) and dye tracer method (AOV), respectively, were used to estimate runoff velocity under three slope gradients (5°, 10°, and 15°) and three slope positions (up-slope, mid-slope, and down-slope). The results showed more variation in runoff velocity under IPV than AOV. Both IPV and AOV were positively correlated with slope gradient. IPV values were close to AOV ones for slope gradients ≤5°, but were significantly different for slope gradients ≥10°. The mean AOV value was 10.6% higher than that of IPV. Regression analysis showed that compared with AOV, IPV overestimated and underestimated runoff under low and high runoff velocity conditions, respectively. The use of image processing in IPV was advantageous because of its ease of use with fewer artificial errors and its suitability for lateral diffusion of runoff. Irrespectively, additional studies are needed to verify and/or improve further the use of this method in runoff velocity analysis.

Author(s):  
Ray Keller

The amphibian embryo offers advantages of size, availability, and ease of use with both microsurgical and molecular methods in the analysis of fundamental developmental and cell biological problems. However, conventional wisdom holds that the opacity of this embryo limits the use of methods in optical microscopy to resolve the cell motility underlying the major shape-generating processes in early development.These difficulties have been circumvented by refining and adapting several methods. First, methods of explanting and culturing tissues were developed that expose the deep, nonepithelial cells, as well as the superficial epithelial cells, to the view of the microscope. Second, low angle epi-illumination with video image processing and recording was used to follow patterns of cell movement in large populations of cells. Lastly, cells were labeled with vital, fluorescent dyes, and their behavior recorded, using low-light, fluorescence microscopy and image processing. Using these methods, the details of the cellular protrusive activity that drives the powerful convergence (narrowing)


Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1631
Author(s):  
Bruno Guilherme Martini ◽  
Gilson Augusto Helfer ◽  
Jorge Luis Victória Barbosa ◽  
Regina Célia Espinosa Modolo ◽  
Marcio Rosa da Silva ◽  
...  

The application of ubiquitous computing has increased in recent years, especially due to the development of technologies such as mobile computing, more accurate sensors, and specific protocols for the Internet of Things (IoT). One of the trends in this area of research is the use of context awareness. In agriculture, the context involves the environment, for example, the conditions found inside a greenhouse. Recently, a series of studies have proposed the use of sensors to monitor production and/or the use of cameras to obtain information about cultivation, providing data, reminders, and alerts to farmers. This article proposes a computational model for indoor agriculture called IndoorPlant. The model uses the analysis of context histories to provide intelligent generic services, such as predicting productivity, indicating problems that cultivation may suffer, and giving suggestions for improvements in greenhouse parameters. IndoorPlant was tested in three scenarios of the daily life of farmers with hydroponic production data that were obtained during seven months of cultivation of radicchio, lettuce, and arugula. Finally, the article presents the results obtained through intelligent services that use context histories. The scenarios used services to recommend improvements in cultivation, profiles and, finally, prediction of the cultivation time of radicchio, lettuce, and arugula using the partial least squares (PLS) regression technique. The prediction results were relevant since the following values were obtained: 0.96 (R2, coefficient of determination), 1.06 (RMSEC, square root of the mean square error of calibration), and 1.94 (RMSECV, square root of the mean square error of cross validation) for radicchio; 0.95 (R2), 1.37 (RMSEC), and 3.31 (RMSECV) for lettuce; 0.93 (R2), 1.10 (RMSEC), and 1.89 (RMSECV) for arugula. Eight farmers with different functions on the farm filled out a survey based on the technology acceptance model (TAM). The results showed 92% acceptance regarding utility and 98% acceptance for ease of use.


2011 ◽  
Vol 347-353 ◽  
pp. 2302-2307 ◽  
Author(s):  
Hong Xiang Wang ◽  
Yi Shi ◽  
Jian Ma ◽  
Cai Yan Lu ◽  
Xin Chen

A field experiment was conducted to study the characteristics of non-point source nitrogen (N) in the surface runoff from sloping croplands and the influences of rainfall and cropland slope gradient. The results showed that dissolved total N (DTN) was the major form of N in the runoff, and the proportion occupied by dissolved inorganic nitrogen (DIN) ranged from 45% to 85%. The level of NH4+-N was generally higher than the level of NO3--N, and averaged at 2.50 mg·L-1and 1.07 mg·L-1respectively. DIN was positively correlated with DTN (R2=0.962). Dissolved organic N (DON) presented a moderate seasonal change and averaged at 1.40 mg·L-1. Rainfall amount and rainfall intensity significantly affected the components of DTN in the runoff. With the increase of rainfall amount and rainfall intensity, the concentrations of DTN, NH4+-N and NO3--N presented a decreased trend, while the concentration of DON showed an increased trend. N loss went up with an increase in the gradient of sloping cropland, and was less when the duration was longer from the time of N fertilization.fertilization.


1974 ◽  
Vol 27 (2) ◽  
pp. 195 ◽  
Author(s):  
HR Skullerud

The motion of electrons in a gas in the presence of large electron density gradients has been studied theoretically, starting from the two-term expansion of the Boltzmann equation. The effects of material boundaries have not been considered. An electron swarm released as a b-function in space and with an equilibrium energy distribution is found initially to develop as a spheroid with dimensions determined by the lateral diffusion coefficient. It subsequently passes through a stage involving a slowly decaying pear-shaped deformation, before ultimately becoming an ellipsoid with dimensions determined by the longitudinal and lateral components of the diffusion tensor. Numerical values cited in the literature for the long-term deviations from the mean square widths predicted by the diffusion equation have been found to be in error by factors of 10 or more.


2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Francisco Aecio Fernandes Dias ◽  
Vinicius Jose Fernandes Dias ◽  
Barbara de Araujo Lima Dutra ◽  
Anna Christina Siqueira Marques ◽  
Edgar Marçal ◽  
...  

Purpose. To develop a mobile app that allows capturing and editing of photographs, performs image transposition and projection of a protractor with 360° axis markings, and permits accurate visualization of programmed alignment for the positioning of toric intraocular lenses (IOLs). Methods. In this prospective case series study, a codesign methodology was chosen to develop the Eye Axis Check application. After app development, measurements were obtained and comparisons were made between manual marks and toric IOL alignment without and with the app in 30 eyes that had undergone cataract surgery with toric IOLs. The mobile app was made available to 15 ophthalmic surgeons in different cities to assess its usability. Results. The users approved the developed application for its ease of use and utility. The mean difference between the markings made manually and those made with the app was 1° (±2°; range: 0°–5°), and the mean difference between the IOL position and the assessment made by the app was 3° (±3°; range: 0°–12°). Upon comparison of the agreement between the app measurements and the manual measurements for the IOL angle, no significant differences were found, and an excellent concordance (0.997) and a strong positive linear correlation (0.995) were observed. Conclusion. A mobile app for preoperative planning and intraoperative toric IOL alignment was developed and revealed to be useful and easy to use.


Symmetry ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2078
Author(s):  
Thuvanan Borvornvitchotikarn ◽  
Werasak Kurutach

Axiomatically, symmetry is a fundamental property of mathematical functions defining similarity measures, where similarity measures are important tools in many areas of computer science, including machine learning and image processing. In this paper, we investigate a new technique to measure the similarity between two images, a fixed image and a moving image, in multi-modal image registration (MIR). MIR in medical image processing is essential and useful in diagnosis and therapy guidance, but still a very challenging task due to the lack of robustness against the rotational variance in the image transformation process. Our investigation leads to a novel, local self-similarity descriptor, called the modality-independent and rotation-invariant descriptor (miRID). By relying on the mean of the intensity values, an miRID is simply computable and can effectively handle the complicated intensity relationship between multi-modal images. Moreover, it can also overcome the problem of rotational variance by sorting the numerical values, each of which is the absolute difference between each pixel’s intensity and the mean of all pixel intensities within a patch of the image. The experimental result shows that our method outperforms others in both multi-modal rigid and non-rigid image registrations.


2013 ◽  
Vol 373-375 ◽  
pp. 694-697 ◽  
Author(s):  
Guang Xun Chen ◽  
Yan Hui Du ◽  
Lei Zhang ◽  
Pan Ke Qin

The commonly used method for high resolution velocity analysis in seismic data processing and interpreting is based on signal estimation algorithm. However, the numerical realization of this method is complicated and time-consuming due to the process of signal-noise separation requiring enormous loop calculations before constructing the energy function. In this paper, we improved the method on the base of multi-trace signal estimation. This improved method made full use of amplitude information that can enhance the anti-noise ability and improve the resolution greatly. Meanwhile, this method has more economical calculation cost than other methods for it didnt require multiple loop calculations.


2013 ◽  
Vol 371 ◽  
pp. 401-405 ◽  
Author(s):  
Dumitru Titi Cicic ◽  
Cătălin Gheorghe Amza ◽  
Diana Popescu ◽  
Florea Dorel Anania

Problem be used for evaluating products quality: - Destructive evaluation, in which the product is destroyed in order to analyse its properties and internal structure; - Non destructive evaluation (NDE), used for identifying defect and irregularities, without damaging the product. These non destructive evaluation methods include [1-4]: ‐ Visual and optical testing – VT; ‐ Magnetic particle testing – MT; ‐ Liquid penetrant testing –PT; ‐ Radiographic testing – RT ; ‐ Ultrasounds testing – UT; ‐ Eddy current testing – ET; One of the most frequently used method of non destructive examination is PT or dye penetrant testing (DPT), due to the low costs involved, ease of use and flexibility, suitability to a large number of applications. This method evaluates the presence of open discontinuities (or cracks) on the surface part, based on reverse capillary action and on the developer absorption effect which draw out penetrant and produces indications visible for the inspector (see fig.1 for a principle scheme of LP examination [5]). Although widely used, PT has several disadvantages: - Limitation to surface defects or to the defects which communicates with the surface; - Only products with non porous surfaces (or with low porosity) can be inspected; - Important amount of time used for manipulating the parts during inspection; - Results interpretation heavily depends on subjective aspects such as operator experience, knowledge and motivation. In order to eliminate or reduce the operator involvement in the process steps, research has being made for automating the process, such examples of liquid penetrant inspection lines can be found in [10-15]. However, in all analysed automated PT systems, the inspection is still made visually by an inspector, who gives a pass/fail grade for the inspected parts. The difficulty of fully automating the liquid penetrant inspection process is due not only to the necessity to precisely determine and control process parameters (dwell time, developer time, drying time, quantity of penetrant, developer and cleaning water, pressure for spraying solutions with penetrant, developer and cleaning water, transport speed, etc.) but also to the evaluation and results interpretation process. Thus, even if there are patents [16-17] which present approaches and general frameworks for fully-automated LPT systems, including also automatic image processing of the flaws, to the best of the authors’ knowledge, these equipment are not yet implemented. In this context, this paper presents an experimental stand for a fully automated liquid penetrant inspection line, which includes the development and use of dedicated imaging software used for real time interpretation of the images acquired using a digital camera. The novelty of the research consist in designing and building a fully-automated LPT stand, controlled by a soft which contains also a module for acquisition and image processing in real time without no human implication.


2021 ◽  
Vol 55 (1) ◽  
Author(s):  
Aubrey Y. Señeris ◽  
Jean Anne B. Toral

Objective. This study aimed to compare the completeness and ease of use of narrative reports (NR) submitted by residents compared to electronic synoptic reports (SR) by gynecologic oncology fellows for patients who underwent ovarian, fallopian, and peritoneal cancer surgery. Methods. We conducted a cross-sectional study in the Department of Obstetrics-Gynecology of the Philippine General Hospital from August to November 2019. We assessed the NRs and electronic SRs for completeness of data using quality indicators. Results. The average percentage of completeness of quality indicators is 77.1% (35.7/65). Eight indicators were absent in all NRs. Reporting of residual lesions was low (29.1%). The mean time to accomplish SRs (10.4 minutes) was significantly shorter than the mean time to accomplish NRs (21.9 minutes) (p value = 0.0001). SRs were assessed to be superior to NRs in several areas of surgery for quality, completeness and timeliness. Conclusion. This study showed that the NRs should be improved and periodic audit must be done to maintain quality assurance. The use of SR appears to be favorable and superior in terms of time required to accomplish.


1976 ◽  
Vol 1 (15) ◽  
pp. 44 ◽  
Author(s):  
Ary Roos ◽  
Jurjen A. Battjes

An experimental study is presented of some characteristic parameters of the flow in the up-rush and down-rush of periodic waves breaking on a plane, smooth slope. The water layer thickness has been measured as a function of time at four locations above still water level. Discharges and particle velocities have been calculated. The results have been made nondimensional on the basis of Hunt's formula for the run-up height. They appear to be either independent of the wave steepness H/L and slope gradient tan Ct or to be a function of a single similarity parameter £ - tana / yH/L only. An hypothesis is stated concerning a relation between the mean rate of overtopping of a dike by waves, and the run-up which would occur under the same circumstances on an uninterrupted slope. On the basis of this hypothesis the overtopping volume per wave can be normalized so as to make it independent of slope angle and wave steepness. A comparison of the result with measurements from other sources indicates a rough agreement.


Sign in / Sign up

Export Citation Format

Share Document