Delineation of Management Zones in Hedgerow Almond Orchards Based on Vegetation Indices from UAV Images Validated by LiDAR-Derived Canopy Parameters

One of the challenges in orchard management, in particular of hedgerow tree plantations, is the delineation of management zones on the bases of high-precision data. Along this line, the present study analyses the applicability of vegetation indices derived from UAV images to estimate the key structural and geometric canopy parameters of an almond orchard. In addition, the classes created on the basis of the vegetation indices were assessed to delineate potential management zones. The structural and geometric orchard parameters (width, height, cross-sectional area and porosity) were characterized by means of a LiDAR sensor, and the vegetation indices were derived from a UAV-acquired multispectral image. Both datasets summarized every 0.5 m along the almond tree rows and were used to interpolate continuous representations of the variables by means of geostatistical analysis. Linear and canonical correlation analyses were carried out to select the best performing vegetation index to estimate the structural and geometric orchard parameters in each cross-section of the tree rows. The results showed that NDVI averaged in each cross-section and normalized by its projected area achieved the highest correlations and served to define potential management zones. These findings expand the possibilities of using multispectral images in orchard management, particularly in hedgerow plantations.

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Assessing the Effect of Real Spatial Resolution of In Situ UAV Multispectral Images on Seedling Rapeseed Growth Monitoring

Remote Sensing ◽

10.3390/rs12071207 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1207 ◽

Cited By ~ 1

Author(s):

Jian Zhang ◽

Chufeng Wang ◽

Chenghai Yang ◽

Tianjin Xie ◽

Zhao Jiang ◽

...

Keyword(s):

Spatial Resolution ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Vegetation Indices ◽

Crop Growth ◽

Growth Monitoring ◽

Multispectral Images ◽

Area Index ◽

Uav Images

The spatial resolution of in situ unmanned aerial vehicle (UAV) multispectral images has a crucial effect on crop growth monitoring and image acquisition efficiency. However, existing studies about optimal spatial resolution for crop monitoring are mainly based on resampled images. Therefore, the resampled spatial resolution in these studies might not be applicable to in situ UAV images. In order to obtain optimal spatial resolution of in situ UAV multispectral images for crop growth monitoring, a RedEdge Micasense 3 camera was installed onto a DJI M600 UAV flying at different heights of 22, 29, 44, 88, and 176m to capture images of seedling rapeseed with ground sampling distances (GSD) of 1.35, 1.69, 2.61, 5.73, and 11.61 cm, respectively. Meanwhile, the normalized difference vegetation index (NDVI) measured by a GreenSeeker (GS-NDVI) and leaf area index (LAI) were collected to evaluate the performance of nine vegetation indices (VIs) and VI*plant height (PH) at different GSDs for rapeseed growth monitoring. The results showed that the normalized difference red edge index (NDRE) had a better performance for estimating GS-NDVI (R2 = 0.812) and LAI (R2 = 0.717), compared with other VIs. Moreover, when GSD was less than 2.61 cm, the NDRE*PH derived from in situ UAV images outperformed the NDRE for LAI estimation (R2 = 0.757). At oversized GSD (≥5.73 cm), imprecise PH information and a large heterogeneity within the pixel (revealed by semi-variogram analysis) resulted in a large random error for LAI estimation by NDRE*PH. Furthermore, the image collection and processing time at 1.35 cm GSD was about three times as long as that at 2.61 cm. The result of this study suggested that NDRE*PH from UAV multispectral images with a spatial resolution around 2.61 cm could be a preferential selection for seedling rapeseed growth monitoring, while NDRE alone might have a better performance for low spatial resolution images.

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Study of the Natural Heritage Condition of the Kursiu Nerija National Park Using Lidar Technology (Case Study of Agila Dune)

Baltic Surveying ◽

10.22616/j.balticsurveying.2019.005 ◽

2019 ◽

Vol 10 ◽

pp. 36-42

Author(s):

Deimante Pankauskyte ◽

Jolanta Valciukiene ◽

Indrius Kuklys ◽

Lina Kukliene

Keyword(s):

Cross Section ◽

Cross Sections ◽

National Park ◽

Large Scale ◽

Precision Data ◽

Protective Measures ◽

Current State ◽

The Status ◽

High Precision Data

Analysis of the condition of the Agila dune is presented in this Article. The analysis is based on data collected during accurate geodetic measurements using LIDAR technology. The current state of the Agila dune was compared to the data of the previous year's LIDAR points in order to ensure the reliability and value of the research. In the course of the study, eleven cross sections were compared by height differences with previous year‘s measurements. The condition of the Agila dune was found to be the worst in three cross sections. First cross section‘s erosion measured at 13,98 meters, erosion in the fifth cross section – 9.90 meters, and erosion in the eighth cross section - 11.34 meters. The main reasons for the deterioration of the natural values of the Kursiu Nerija National Park are climate, wind, high visitor flows and the persistent failure to carry out comprehensive research. Therefore, in order to preserve these unique natural values, it is important to collect large-scale and high-precision data on the status of these values, to systematize, analyze and take appropriate protective measures.

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USING UAVs/DRONES AND VEGETATION INDICES IN THE VISIBLE SPECTRUM TO MONITORING AGRICULTURAL LANDS

IRAQI JOURNAL OF AGRICULTURAL SCIENCES ◽

10.36103/ijas.v52i3.1349 ◽

2021 ◽

Vol 52 (3) ◽

pp. 601-610

Author(s):

Qubaa & et al.

Keyword(s):

Vegetation Index ◽

Agricultural Land ◽

Vegetation Indices ◽

Visible Spectrum ◽

Agricultural Field ◽

Smart Systems ◽

Different Types ◽

Management And Development ◽

Uav Images ◽

First Time

Unmanned Aerial Vehicles UAVs or Drones have made great progress in the field of aerial surveys to study vegetation and farmland. The research focuses on developing smart systems for managing agricultural fields, thus facilitating decision-making, increasing agricultural productivity, improving profitability and protecting the environment. The paper highlights the ability of drones to distinguish agricultural land intended for cultivation and classified as deserted or cultivated or in the germination stage. For the first time in the Nineveh governorate, a Phantom 4 DJI UAV images were used, in addition to using the spatialized Pix4Dfielde program to process these images. Four types of the standard agricultural indices that rely on the visible spectrum have been used (Visible Atmospherically Resistant Index (VARI), Triangular Greenness Index (TGI), Synthetic Normalized Differences Vegetation Index (S-NDVI) and Visible Difference Vegetation Index (VDVI)) to test UAVs images and to categorize different types of agricultural land. The results showed that when using the S-NDVI and VDVI indicators, the values 0.16 and 0.14 appeared respectively in certain areas, which indicates the presence and integrity of vegetation cover, unlike other regions, whose indicators showed 0.010 and -0.004, respectively, which indicate that the plant has a bad condition or its absence at all. All results finding in this research reflect and confirm the validity of using UAVs images for agricultural field management and development.

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Mass Determination by Direct Measurement of Electron Scattering

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114827 ◽

1975 ◽

Vol 33 ◽

pp. 240-241

Author(s):

M. K. Lamvik ◽

A. V. Crewe

Keyword(s):

Cross Section ◽

Electron Scattering ◽

Mass Density ◽

Variable Mass ◽

Scattering Cross Section ◽

Mass Determination ◽

Number Density ◽

Cross Sectional ◽

Thin Slice ◽

Scattering Cross

If a molecule or atom of material has molecular weight A, the number density of such units is given by n=Nρ/A, where N is Avogadro's number and ρ is the mass density of the material. The amount of scattering from each unit can be written by assigning an imaginary cross-sectional area σ to each unit. If the current I0 is incident on a thin slice of material of thickness z and the current I remains unscattered, then the scattering cross-section σ is defined by I=IOnσz. For a specimen that is not thin, the definition must be applied to each imaginary thin slice and the result I/I0 =exp(-nσz) is obtained by integrating over the whole thickness. It is useful to separate the variable mass-thickness w=ρz from the other factors to yield I/I0 =exp(-sw), where s=Nσ/A is the scattering cross-section per unit mass.

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A tilting high temperature gas reaction chamber for the JEM 7A T.E.M.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107496 ◽

1978 ◽

Vol 36 (1) ◽

pp. 70-71

Author(s):

Brian L. Rhoades

Keyword(s):

Cross Section ◽

Reaction Chamber ◽

Objective Lens ◽

Reduced Cross Section ◽

Cross Sectional ◽

Structural Investigations ◽

Transmission Electron ◽

Dynamic Experiments ◽

Successful Design ◽

Thermocouple Junction

A gas reaction chamber has been designed and constructed for the JEM 7A transmission electron microscope which is based on a notably successful design by Hashimoto et. al. but which provides specimen tilting facilities of ± 15° aboutany axis in the plane of the specimen.It has been difficult to provide tilting facilities on environmental chambers for 100 kV microscopes owing to the fundamental lack of available space within the objective lens and the scope of structural investigations possible during dynamic experiments has been limited with previous specimen chambers not possessing this facility.A cross sectional diagram of the specimen chamber is shown in figure 1. The specimen is placed on a platinum ribbon which is mounted on a mica ring of the type shown in figure 2. The ribbon is heated by direct current, and a thermocouple junction spot welded to the section of the ribbon of reduced cross section enables temperature measurement at the point where localised heating occurs.

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Microstructure of laser-irradiated, conducting Kapton polyimide

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138889 ◽

1995 ◽

Vol 53 ◽

pp. 502-503

Author(s):

D. L. Callahan ◽

Z. Ball ◽

H. M. Phillips ◽

R. Sauerbrey

Keyword(s):

Electron Microscopy ◽

Phase Transition ◽

Transmission Electron Microscopy ◽

Cross Section ◽

Film Surface ◽

Cross Sectional ◽

General Utility ◽

Transmission Electron ◽

Considerable Debate ◽

Potential Applications

Ultraviolet laser-irradiation can be used to induce an insulator-to-conductor phase transition on the surface of Kapton polyimide. Such structures have potential applications as resistors or conductors for VLSI applications as well as general utility electrodes. Although the percolative nature of the phase transformation has been well-established, there has been little definitive work on the mechanism or extent of transformation. In particular, there has been considerable debate about whether or not the transition is primarily photothermal in nature, as we propose, or photochemical. In this study, cross-sectional optical microscopy and transmission electron microscopy are utilized to characterize the nature of microstructural changes associated with the laser-induced pyrolysis of polyimide.Laser-modified polyimide samples initially 12 μm thick were prepared in cross-section by standard ultramicrotomy. Resulting contraction in parallel to the film surface has led to distortions in apparent magnification. The scale bars shown are calibrated for the direction normal to the film surface only.

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Profil Penyakit Malaria Di Rumah Sakit Islam Siti Rahmah Padang Tahun 2018

Health & Medical Journal ◽

10.33854/heme.v2i2.546 ◽

2020 ◽

Vol 2 (2) ◽

pp. 08-15

Author(s):

Rahma Triyana ◽

Salmi Salmi

Keyword(s):

Observational Study ◽

Frequency Distribution ◽

Cross Section ◽

Laboratory Tests ◽

Age Group ◽

Normal Range ◽

Cross Sectional ◽

West Sumatra ◽

Severity Of The Disease

Malaria is one of the health problems in Indonesia, especially West Sumatra. Determination of the description of Malaria disease in an area is needed to determine the spread and severity of the disease. This study aims to determine the frequency distribution according to age, sex and place of residence, description of the types of Plasmodium causes of Malaria and hematological features in Malaria patients at Siti Rahmah Padang Hospital in 2018. This type of research is a descriptive observational study with an approach or design cross section (cross sectional). The frequency distribution of Malaria sufferers in Siti Rahmah Padang Hospital in 2018 according to the highest age was in the age group 21-30 years as many as 28 cases (36.8%), the highest sex among men was 46 (60.5%) and the highest number of residences was found in Koto Tangah sub-district there were 31 cases (40.8%). The type of Plasmodium found in Malaria cases in Siti Rahmah Padang Hospital in 2018 was P. vivax (73 cases (96.05%)) and P. falciparum (3 cases (3.95%)). The results of laboratory tests on Hb, hematocrit, platelet and leukocyte levels in Malaria positive patients in Siti Rahmah Padang Hospital in 2018 were in the normal range.

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Profil Penyakit Malaria di Rumah Sakit Islam Siti Rahmah Padang Tahun 2018

Health & Medical Journal ◽

10.33854/heme.v2i2.452 ◽

2020 ◽

Vol 2 (2) ◽

pp. 08-15

Author(s):

Rahma Triyana Y ◽

Salmi Salmi

Keyword(s):

Observational Study ◽

Frequency Distribution ◽

Cross Section ◽

Laboratory Tests ◽

Age Group ◽

Normal Range ◽

Cross Sectional ◽

West Sumatra ◽

Severity Of The Disease

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HEALTHINESS OF OIL PALM PLANTATION TOWARDS SUSTAINABILITY OF ENVIRONMENT

Malaysian Journal of Sustainable Environment ◽

10.24191/myse.v7i1.8905 ◽

2020 ◽

Vol 7 (1) ◽

pp. 21

Author(s):

Faradina Marzukhi ◽

Nur Nadhirah Rusyda Rosnan ◽

Md Azlin Md Said

Keyword(s):

Oil Palm ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Satellite Image ◽

Vegetation Indices ◽

Soil Nutrient ◽

Oil Palm Plantation ◽

Sustainable Environment ◽

Moisture Analysis ◽

The Relationship

The aim of this study is to analyse the relationship between vegetation indices of Normalized Difference Vegetation Index (NDVI) and soil nutrient of oil palm plantation at Felcra Nasaruddin Bota in Perak for future sustainable environment. The satellite image was used and processed in the research. By Using NDVI, the vegetation index was obtained which varies from -1 to +1. Then, the soil sample and soil moisture analysis were carried in order to identify the nutrient values of Nitrogen (N), Phosphorus (P) and Potassium (K). A total of seven soil samples were acquired within the oil palm plantation area. A regression model was then made between physical condition of the oil palms and soil nutrients for determining the strength of the relationship. It is hoped that the risk map of oil palm healthiness can be produced for various applications which are related to agricultural plantation.

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Access of Key Population to Available HIV and TB Services in Nepal: A Cross Section Study

SAARC Journal of Tuberculosis Lung Diseases and HIV/AIDS ◽

10.3126/saarctb.v17i1.25024 ◽

2019 ◽

Vol 17 (1) ◽

pp. 17-23

Author(s):

B.B. Subba ◽

N. Rimal ◽

B.M. Shrestha

Keyword(s):

Viral Load ◽

Cross Section ◽

General Knowledge ◽

Cross Sectional Survey ◽

Cross Sectional ◽

Key Population ◽

Mdr Tb ◽

Study Population ◽

Control And Management ◽

Structured Questionnaire

Introduction: TB is considered one of the opportunistic infection among PLHIV. The increasing burden of HIV/TB co-infection among key population cause problem to maintain adherence to ART and DOTS services. The emergence of MDR-TB is one of the greatest challenge to control and management of both diseases. However, having knowledge and information of both diseases are important role to access the available HIV/TB services. Methods: A cross-sectional survey was conducted among key population who had HIV/TB co-infection in two-epidemic zone of Nepal. A pretested semi-structured questionnaire was used to collect data. ANOVA test was done to analyze the collected data by using SPSS version 20.0. Results: A total of 343 HIV/TB co-infected individuals were enrolled to the study. Most of participants were from ART and DOTS clients. Therefore, the study found that there was significance difference found between knowledge about TB (F=4.400, p= 0.005), causative agent of TB (F=3.160, p=0.025), risk of TB illness among PLHIV (F=8.491, p=0.001) and among key affected population. Moreover, there was significance difference found between access to OI treatment (F=5.113, p=0.002) and access to viral load (F=4.642, p=0.003) among key study population. In gender perspective, there was no significance difference to use and access to available HIV/TB services. Conclusion: The general knowledge on HIV/TB co-infection was significant association with key population. The knowledge on HIV/TB and access to NGOs’ help can significant effect to access the available HIV and TB services.

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