scholarly journals Comparison of RGB and Multispectral Unmanned Aerial Vehicle for Monitoring Vegetation Coverage Changes on a Landslide Area

Drones ◽  
2021 ◽  
Vol 5 (3) ◽  
pp. 97
Author(s):  
Flavio Furukawa ◽  
Lauretta Andrew Laneng ◽  
Hiroaki Ando ◽  
Nobuhiko Yoshimura ◽  
Masami Kaneko ◽  
...  
Keyword(s):  
Image Quality ◽  
Bare Soil ◽  
Vegetation Coverage ◽  
Landslide Area ◽  
Vegetation Monitoring ◽  
Precise Information ◽  
Different Types ◽  
Aerial Vehicle ◽  
Vegetation Class ◽  
Over Time

The development of UAV technologies offers practical methods to create landcover maps for monitoring and management of areas affected by natural disasters such as landslides. The present study aims at comparing the capability of two different types of UAV to deliver precise information, in order to characterize vegetation at landslide areas over a period of months. For the comparison, an RGB UAV and a Multispectral UAV were used to identify three different classes: vegetation, bare soil, and dead matter, from April to July 2021. The results showed high overall accuracy values (>95%) for the Multispectral UAV, as compared to the RGB UAV, which had lower overall accuracies. Although having lower overall accuracies, the vegetation class of the RGB UAV presented high producer’s and user’s accuracy over time, comparable to the Multispectral UAV results. Image quality played an important role in this study, where higher accuracy values were found on cloudy days. Both RGB and Multispectral UAVs presented similar patterns of vegetation, bare soil, and dead matter classes, where the increase in vegetation class was consistent with the decrease in bare soil and dead matter class. The present study suggests that the Multispectral UAV is more suitable in characterizing vegetation, bare soil, and dead matter classes on landslide areas while the RGB UAV can deliver reliable information for vegetation monitoring.

Measuring Agency Change Across the Domain of Hypnosis

2019 ◽  
Author(s):  
Vince Polito ◽  
Amanda Barnier ◽  
Erik Woody
Keyword(s):  
Rating Scale ◽  
Sense Of Agency ◽  
Pass Rates ◽  
Current Experiment ◽  
Multidimensional Construct ◽  
Time Points ◽  
Hypnotic Induction ◽  
Different Types ◽  
Over Time ◽  
Postexperimental Inquiry

Building on Hilgard’s (1965) classic work, the domain of hypnosis has been conceptualised by Barnier, Dienes, and Mitchell (2008) as comprising three levels: (1) classic hypnotic items, (2) responding between and within items, and (3) state and trait. The current experiment investigates sense of agency across each of these three levels. Forty-six high hypnotisable participants completed an ideomotor (arm levitation), a challenge (arm rigidity) and a cognitive (anosmia) item either following a hypnotic induction (hypnosis condition) or without a hypnotic induction (wake condition). In a postexperimental inquiry, participants rated their feelings of control at three time points for each item: during the suggestion, test and cancellation phases. They also completed the Sense of Agency Rating Scale (Polito, Barnier, & Woody, 2013) for each item. Pass rates, control ratings, and agency scores fluctuated across the different types of items and for the three phases of each item; also, control ratings and agency scores often differed across participants who passed versus failed each item. Interestingly, whereas a hypnotic induction influenced the likelihood of passing items, it had no direct effect on agentive experiences. These results suggest that altered sense of agency is not a unidimensional or static quality “switched on” by hypnotic induction, but a dynamic multidimensional construct that varies across items, over time and according to whether individuals pass or fail suggestions.

Imagery in the Book of Revelation

2020 ◽  
pp. 52-67
Author(s):  
Konrad Huber
Keyword(s):  
Reception History ◽  
Book Of Revelation ◽  
Imperial Cult ◽  
Emotional Effect ◽  
Greco Roman ◽  
Different Types ◽  
Figurative Speech ◽  
Theological Message ◽  
Over Time ◽  
The Way

The chapter first surveys different types of figurative speech in Revelation, including simile, metaphor, symbol, and narrative image. Second, it considers the way images are interrelated in the narrative world of the book. Third, it notes how the images draw associations from various backgrounds, including biblical and later Jewish sources, Greco-Roman myths, and the imperial cult, and how this enriches the understanding of the text. Fourth, the chapter looks at the rhetorical impact of the imagery on readers and stresses in particular its evocative, persuasive, and parenetic function together with its emotional effect. And fifth, it looks briefly at the way reception history shows how the imagery has engaged readers over time. Thus, illustrated by numerous examples, it becomes clear how essentially the imagery of the book of Revelation constitutes and determines its theological message.

scholarly journals The Effects of Roadside Woody Vegetation on the Surface Temperature of Cycle Paths

Land ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 483
Author(s):  
Nikola Žižlavská ◽  
Tomáš Mikita ◽  
Zdeněk Patočka
Keyword(s):  
Solar Radiation ◽  
Surface Temperature ◽  
Well Being ◽  
Road Surface ◽  
Woody Vegetation ◽  
Surface Model ◽  
Main Hypothesis ◽  
Roadside Vegetation ◽  
Different Types ◽  
Aerial Vehicle

The article is on the effects of woody vegetation growing on the roadside on the temperature of the surface of cycle paths. The main hypothesis of the study is that vegetation has the effect of lowering the temperature of the surroundings in its shadow and thus improves the comfort of users of cycle paths in the summer months. The second hypothesis is to find out which type of road surface is most suitable for the thermal well-being of users. This goal was achieved by measuring the temperature of selected locations on cycle paths with different types of construction surfaces with nearby woody vegetation using a contactless thermometer over several days at regular intervals. The positions of the selected locations were measured using GNSS and the whole locality of interest was photographed using an unmanned aerial vehicle (UAV), or drone, and subsequently a digital surface model (DSM) of the area was created using a Structure from Motion (SfM) algorithm. This model served for the calculation of incident solar radiation during the selected days using the Solar Area Graphics tool with ArcGIS software. Subsequently, the effect of the shade of the surrounding vegetation on the temperature during the day was analysed and statistically evaluated. The results are presented in many graphs and their interpretation used to evaluate the effects of nearby woody vegetation and the type of road surface on the surrounding air temperature and the comfort of users of these routes. The results demonstrate the benefits of using UAVs for the purpose of modelling the course of solar radiation during the day, showing the effect of roadside vegetation on reducing the surface temperature of the earth’s surface and thus confirming the need for planting and maintaining such vegetation.

scholarly journals Using UAV LiDAR to Extract Vegetation Parameters of Inner Mongolian Grassland

2021 ◽  
Vol 13 (4) ◽  
pp. 656
Author(s):  
Xiang Zhang ◽  
Yuhai Bao ◽  
Dongliang Wang ◽  
Xiaoping Xin ◽  
Lei Ding ◽  
...  
Keyword(s):  
Major Effect ◽  
Canopy Height ◽  
Vegetation Coverage ◽  
Accurate Estimation ◽  
Grassland Vegetation ◽  
Pixel Resolution ◽  
Aerial Vehicle ◽  
Grazing Intensities ◽  
Vegetation Parameters ◽  
Mongolian Grassland

The accurate estimation of grassland vegetation parameters at a high spatial resolution is important for the sustainable management of grassland areas. Unmanned aerial vehicle (UAV) light detection and ranging (LiDAR) sensors with a single laser beam emission capability can rapidly detect grassland vegetation parameters, such as canopy height, fractional vegetation coverage (FVC) and aboveground biomass (AGB). However, there have been few reports on the ability to detect grassland vegetation parameters based on RIEGL VUX-1 UAV LiDAR (Riegl VUX-1) systems. In this paper, we investigated the ability of Riegl VUX-1 to model the AGB at a 0.1 m pixel resolution in the Hulun Buir grazing platform under different grazing intensities. The LiDAR-derived minimum, mean, and maximum canopy heights and FVC were used to estimate the AGB across the entire grazing platform. The flight height of the LiDAR-derived vegetation parameters was also analyzed. The following results were determined: (1) The Riegl VUX-1-derived AGB was predicted to range from 29 g/m2 to 563 g/m2 under different grazing conditions. (2) The LiDAR-derived maximum canopy height and FVC were the best predictors of grassland AGB (R2 = 0.54, root-mean-square error (RMSE) = 64.76 g/m2). (3) For different UAV flight altitudes from 40 m to 110 m, different flight heights showed no major effect on the derived canopy height. The LiDAR-derived canopy height decreased from 9.19 cm to 8.17 cm, and the standard deviation of the LiDAR-derived canopy height decreased from 3.31 cm to 2.35 cm with increasing UAV flight altitudes. These conclusions could be useful for estimating grasslands in smaller areas and serving as references for other remote sensing datasets for estimating grasslands in larger areas.

scholarly journals Effect of scent on comfort of aircraft passengers

Work ◽  
2021 ◽  
Vol 68 (s1) ◽  
pp. S273-S280
Author(s):  
Xinhe Yao ◽  
Yu Song ◽  
Peter Vink
Keyword(s):  
Completion Time ◽  
Aircraft Cabin ◽  
Different Types ◽  
The Relationship ◽  
Over Time

BACKGROUND: Scents may influence the perceived comfort of an environment. There are only a few studies conducted on the relationship between scent and comfort in aircraft cabin. OBJECTIVES: The goal of this research is to explore whether relationships between scents and perceived comfort can be found for passengers in an aircraft cabin. METHODS: 276 participants joined an experiment in a Boeing 737 fuselage. The participants were divided into nine groups and each joined a session for 60 minutes with the exposure to different scents. The effect of the odor was measured by a set of questionnaires at the beginning and at the end of the session. Results of questionnaires were analyzed regarding the effects on the completion time, of the type of scents, of the intensity of the scent and on gender. RESULTS: Significant differences were found at the beginning and at the end of the experiment regarding comfort and emotion, but sometimes no relations could be established. The influence of different scents on comfort/discomfort varied and changed over time. However, in all scenarios, participant’ scores on emotion decreased. Additionally, the added scents influenced the linearity between the changes in comfort and discomfort. CONCLUSIONS: Smell could influence the perceived comfort/discomfort of aircraft passengers over time, and different types of smells have different effects on passengers. The preferences on scents are diverse, which highlights the need for personalization in aircraft cabin design.

scholarly journals Estimation of contrast-to-noise ratio in CT and CBCT images with varying scan settings in presence of different implant materials

2019 ◽  
Vol 48 (8) ◽  
pp. 20190139
Author(s):  
Emine Şebnem Kursun-Cakmak ◽  
Husniye Demirturk Kocasarac ◽  
Seval Bayrak ◽  
Gülbahar Ustaoğlu ◽  
Marcel Noujeim
Keyword(s):  
Image Quality ◽  
Imaging Modality ◽  
Cone Beam Ct ◽  
Medical Systems ◽  
Plastic Container ◽  
Implant Materials ◽  
Different Types ◽  
Noise Ratio ◽  
Titanium Grade ◽  
Imagej Software

Objectives: To assess the contrast-to-noise ratio (CNR) of four different types of dental implant materials in CT and cone beam CT (CBCT) images with varying scan settings. Methods: Four different types of implants: zirconium (Zr), titanium (Ti) Grade 4 and 5 and titanium–zirconium (Ti–ZrO2) alloy were placed in a 3% gelatin phantom in a cylindrical plastic container and scanned with two different CT machines (GE Medical systems and Toshiba Medical Systems) and one CBCT machine (I-CAT, Imaging Sciences International) with different voxel sizes of 0.2, 0.25, 0.3 and 0.4 mm. Images were analyzed using ImageJ software with the purpose of estimating the CNR. Results: The CNR obtained from images acquired with CT was lower than the CBCT with all voxel sizes tested. 0.3 and 0.4 mm voxel sizes exhibited the highest CNR (p < 0.05) that gives the best image quality. Among the implant materials tested, titanium Grade 5 has the highest levels of CNR while Zirconium has the lowest (p < 0.05). Conclusions: The optimum protocol for radiographic follow-up in areas near implants on the I-CAT is low-resolution settings (0.3 and 0.4 mm voxel sizes) which gave the highest CNR thus image quality. In presence of Zr implants, an alternative imaging modality (i.e., MRI) may be considered to avoid low-quality images.

Canadian Exceptionalism: Explaining Differences over Time in Provincial and Federal Voter Turnout

2001 ◽  
Vol 34 (2) ◽  
pp. 299-319 ◽  
Author(s):  
Donley T. Studlar
Keyword(s):  
Regression Analysis ◽  
Population Density ◽  
Multiple Regression Analysis ◽  
Voter Turnout ◽  
The Political ◽  
Federal Level ◽  
Industrial Democracies ◽  
Different Types ◽  
Over Time ◽  
Cross National

Canada is unusual among advanced industrial democracies in having some provinces which regularly have greater voter turnouts for provincial than for federal elections. Provincial and federal turnouts by province in Canada are analyzed for the 1945-1998 period using multiple regression analysis, both for each set of elections and by comparing differences between the two. Federal turnout has declined over the years but provincial turnout appears to have increased slightly. Although the effects found here largely confirm previous findings about the relative effects of different types of variables found for the Canadian federal level only, several of the political explanations previously supported in cross-national research find less support. Instead, region, population density, months since the last federal or provincial election, and season of the year generally have greater and sometimes more consistent effects. This suggests the need for more studies of turnout in democracies at sub-central levels.

scholarly journals Tracking the Evolution of Riverbed Morphology on the Basis of UAV Photogrammetry

2021 ◽  
Vol 13 (4) ◽  
pp. 829
Author(s):  
Teresa Gracchi ◽  
Guglielmo Rossi ◽  
Carlo Tacconi Stefanelli ◽  
Luca Tanteri ◽  
Rolando Pozzani ◽  
...  
Keyword(s):  
Management Practices ◽  
Low Cost ◽  
3D Models ◽  
Vegetation Coverage ◽  
Detection Analysis ◽  
Digital Terrain ◽  
Fluvial Dynamics ◽  
Aerial Vehicle ◽  
One Year ◽  
Short Time

Unmanned aerial vehicle (UAV) photogrammetry has recently become a widespread technique to investigate and monitor the evolution of different types of natural processes. Fluvial geomorphology is one of such fields of application where UAV potentially assumes a key role, since it allows for overcoming the intrinsic limits of satellite and airborne-based optical imagery on one side, and in situ traditional investigations on the other. The main purpose of this paper was to obtain extensive products (digital terrain models (DTMs), orthophotos, and 3D models) in a short time, with low costs and at a high resolution, in order to verify the capability of this technique to analyze the active geomorphic processes on a 12 km long stretch of the French–Italian Roia River at both large and small scales. Two surveys, one year apart from each other, were carried out over the study area and a change detection analysis was performed on the basis of the comparison of the obtained DTMs to point out and characterize both the possible morphologic variations related to fluvial dynamics and modifications in vegetation coverage. The results highlight how the understanding of different fluvial processes may be improved by appropriately exploiting UAV-based products, which can thus represent a low-cost and non-invasive tool to crucially support decisionmakers involved in land management practices.

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