coveR: An R package for processing Digital Cover Photography images to retrieve forest canopy attributes

Digital Cover Photography (DCP) is an increasingly popular tool for estimating canopy cover and leaf area index (LAI). However, existing solutions to process canopy images are predominantly tailored for fisheye photography, whereas open-access tools for DCP are lacking. We developed an R package (coveR) to support the whole processing of DCP images in an automated, fast and reproducible way. The package functions, which are designed for step-by-step single-image analysis, can be performed sequentially in a pipeline and also allow simple implementation of batch-processing bunches of images. A case study is presented to demonstrate the reliability of canopy attributes derived from coveR in pure beech (Fagus sylvatica L.) stands with variable canopy density and structure. Estimates of gap fraction and effective LAI from DCP were validated against reference measurements obtained from terrestrial laser scanning. By providing a simple, transparent and flexible image processing procedure, coveR supported the use of DCP for routine measurements and monitoring of forest canopy attributes. This, combined with the implementability of DCP in many devices, including smartphones, micro-cameras, and remote trail cameras, can greatly expand the accessibility of the method also to non-experts.

Remote Sensing Detection of Algal Blooms in a Lake Impacted by Petroleum Hydrocarbons

The purpose of this study was to combine all available information on the state of Lake Pertusillo (Basilicata, Italy), both in the field and published, which included Sentinel-2A satellite data, to understand algal blooms in a lacustrine environment impacted by petroleum hydrocarbons. Sentinel-2A data was retrospectively used to monitor the state of the lake, which is located near the largest land-based oil extraction plant in Europe, with particular attention to chlorophyll a during algal blooms and petroleum hydrocarbons. In winter 2017, a massive dinoflagellate bloom (10.4 × 106 cell/L) of Peridinium umbonatum and a simultaneous presence of hydrocarbons were observed at the lake surface. Furthermore, a recent study using metagenomic analyses carried out three months later identified a hydrocarbonoclastic microbial community specialized in the degradation aromatic and nitroaromatic hydrocarbons. In this study, Sentinel-2A imagery was able to detect the presence of chlorophyll a in the waters, while successfully distinguishing the signal from that of hydrocarbons. Remotely sensed results confirmed surface reference measurements of lacustrine phytoplankton, chlorophyll a, and the presence of hydrocarbons during algal blooms, thereby explaining the presence of the hydrocarbonoclastic microbial community found in the lake three months after the oil spill event. The combination of emerging methodologies such as satellite systems and metagenomics represent an important support methodology for describing complex contaminations in diverse ecosystems.

A New Viscosity and Density Sensing Platform for Drilling Automation

During drilling operations, measurements of drilling fluid/mud viscosity and density provide key information to ensure safe operations (e.g., maintain wellbore integrity) and improve the rate of penetration (e.g., maintain proper hole cleaning). Nowadays, these measurements are still performed manually by using a calibrated funnel viscometer and a weight balance, as stipulated by current American Petroleum Institute (API) standards. In this study, we introduce an automated viscosity/density measurement system based on an electromechanical tuning fork resonator. The system allows for continuous measurements as fast as several times per second in a compact footprint, allowing it to be deployed in tanks or pipelines and/or gathering data from multiple sensors in the mud circulation system. The streams of data produced were broadcasted to a nearby computer allowing for live monitoring of the viscosity and density. The results obtained by the in-tank system in five wells were in good agreement with the standard reference measurements from the mud logs. Here, we describe the development and testing of the tool as well as general guidelines for integration into a rig edge-computing system for real-time analytics and detection of operational problems and drilling automation.

Estimation of Pesticide Residues on Leafy Vegetables Using a Developed Handheld Spectrometer

In this study, a rapid and non-destructive detection model for pesticide residues on leafy vegetables was presented using a developed portable spectrometer. VIS/NIR spectra of three vegetable samples, including lettuce, oriental mustard, and bok choy, were analyzed at the range of 380 – 840 nm. Stepwise multiple linear regression (SMLR) models were developed based on chemical reference measurements and the spectral information of the leaf samples after performing the pre-processing method. Furthermore, a data acquisition interface was developed by Matlab GUI. Results of SMLR procedure indicated good performance for detection of indoxacarb and chlorantraniliprole with R2 ≥ 0.90. A fairly good model (0.90 > R2 > 0.80) was obtained for carbendazim in lettuce, whereas a poor model was found for emamectin-benzoate with R2 ≤ 0.80. It was concluded that pesticide residues on leafy vegetables could be predicted using our developed handheld spectrometer. It can also be generalized for the prediction of other pesticide components in agricultural products.

Field Setup and Assessment of a Cloud-Data Based Crane Scale (CCS) Considering Weight- and Local Green Wood Density-Related Volume References

When investigating the forwarding process within the timber supply chain, insufficient data often inhibits long-term studies or make real-time optimisation of the logistics process difficult. Information sources to compensate for this lack of data either depend on other processing steps or they need additional, costly hardware, such as conventional crane scales. An innovative weight-detection concept using information provided by a commonly available hydraulic pressure sensor may make the introduction of a low-cost weight information system possible. In this system, load weight is estimated by an artificial neural network (ANN) based on machine data such as the hydraulic pressure of the inner boom cylinder and the grapple position.In our study, this type of crane scale was set up and tested under real working conditions, implemented as a cloud application. The weight scale ANN algorithm was therefore modified for robustness and executed on data collected with a commonly available telematics module. To evaluate the system, also with regard to larger sample sizes, both direct weight-reference measurements and additional volume-reference measurements were made. For the second, locally valid weight-volume conversion factors for mainly Norway spruce (Picea abies, 906 kg m-3, standard error of means (SEM) of 13.6 kg m-3), including mean density change over the observation time (–0.16% per day), were determined and used as supportive weight-to-volume conversion factor.Although the accuracy of the weight scale was lower than in previous laboratory tests, the system showed acceptable error behaviour for different observation purposes. The twice-observed SEM of 1.5% for the single loading movements (n=95, root-mean-square error (RMSE) of 15.3% for direct weight reference; n=440, RMSE=33.2% for volume reference) enables long-term observations considering the average value, but the high RMSE reveals problems with regard to the single value information.The full forwarder load accuracy, as unit of interest, was observed with an RMSE of 10.6% (n=41), considering a calculated weight-volume conversion as reference value. An SEM of 5.1% for already five observations with direct weight reference provides a good starting point for work-progress observation support.

Evaluating the Accuracy of Remote Dendrometers in Tree Diameter Measurements at Breast Height

An accurate tree diameter (DBH) measurement is a significant component of forest inventory. This study assessed the reliability of remote dendrometers to measure tree DBH. We compared direct caliper measurements (reference measurements) to the remote measurements collected from a laser caliper and a smartphone at 0.5 m, 1 m, and 1.5 m distances from each tree within three forest types (pine, oak, and poplar forests). In general, all remote dendrometers underestimated the mean diameter compared to direct caliper measurements, regardless of forest types and distances. We observed that the mean deviation of direct caliper measurement and smartphone measurement at 1.5 m within a pine forest and oak forest were the lowest (0.3 cm and 0.36 cm, respectively). The deviations between direct caliper measurements and smartphone measurements at a 0.5 m distance, across forest types, were noticeably larger compared to others. An ANOVA test was used to determine whether significant deviations existed between caliper measurements and remote measurements at a specific distance, and among three different forest types. We rejected the null hypothesis, which suggested that there were no statistically significant differences (p<0.05) between tree DBH measurements obtained from the direct caliper measurements and indirect measurements (smartphone and laser caliper) captured at a distance. Then, a post-hoc test was performed to examine which set of estimated deviations was different from the reference data. The results suggested that indirect tree DBH measurements using the smartphone app at 1 m and 1.5 m in certain forest types (pine and oak) were not significantly different from direct tree DBH measurements. Also, our test results mostly indicated no significant difference within each forest, except for measurements using the smartphone app at 0.5 m across all forest types when the smartphone measurements were compared to laser caliper measurements. Although forest characteristics and measurement distance may play an important role in remote tree DBH measurement accuracy, the smartphone app may be used as a practical alternative to direct measurement in measuring the DBH of a tree, which may be a positive development for forestry due to the increased use of smartphones and the availability of a free measure app.

STUDI PERBANDINGAN ANALISA KETELITIAN TINGGI MENGGUNAKAN TOTAL STATION DAN SIPAT DATAR

This research was conducted to analyze and determine the height difference accuracy using the method of measuring the different heights of a closed loop using Waterpass B2 and Total Station Kolida 420SR. The location of research in the Ciloto area, Puncak, West Java with coordinates 107˚ east longitude and 06˚ south latitude, on 14-15 December 2014 using a local high point reference. Measurements were made three times with different looped but the starting and ending points were the same points. Accuracy of calculation is done by calculating the average of the least squares to determine the standard deviation of the measurement results with each equipment. The result is the standard deviation of the height difference with the waterpass is 0.01mm, while with the Total Station it is 0.02 mm. Based on the results of the standard deviation of the height difference, the Total Station can be used for height measurements in civil engineering project that does not require very high accuracy and height difference measurements with the Total Station are more economical because the time required for measurement is a quarter of the time required height difference measurement with Waterpass. Keywords: height measurement; Waterpass; Total station. AbstrakPenelitian ini dilakukan untuk menganalisis dan mengetahui ketelitian beda tinggi menggunakan metode pengukuran beda tinggi suatu ring tertutup menggunakan Waterpass B2 dan Total Station Kolida 420SR. Lokasi penelitian terletak di daerah Ciloto, Puncak Jawa Barat dengan koordinat 107o bujur timur dan 06o lintang selatan, pada tanggal 14 dan 15 Desember 2014 dengan menggunakan referensi titik tinggi lokal. Pengukuran dilakukan tiga kali dengan ring yang berbeda namun titik pangkal dan ujung adalah titik yang sama. Hitungan ketelitian dilakukan dengan hitung perataan kuadrat terkecil untuk mengetahui standar deviasi hasil pengukuran dengan masing-masing alat. Hasilnya adalah standar deviasi beda tinggi dengan waterpass sebesar 0.01mm, sedangkan dengan Total Station sebesar 0.02 mm. Berdasarkan hasil perhitungan nilai standar deviasi pengukuran beda tinggi, maka Total Station dapat digunakan untuk pengukuran beda tinggi pada pekerjaan teknik sipil yang tidak memerlukan ketelitian yang sangat tinggi, dan pengukuran beda tinggi dengan Total Station lebih ekonomis karena waktu yang diperlukan untuk pengukuran adalah seperempat dari waktu yang diperlukan pengukuran beda tinggi dengan Waterpass.

A Comparison of Different Natural Groundwaters from Repository Sites—Corrosivity, Chemistry and Microbial Community

In Finland, the repositories for low and intermediate-level radioactive waste (LLW and ILW) will be situated at three different geographical locations in about 60 to 100 m deep granite bedrock where the waste and waste containers can be subjected to anoxic groundwater containing microbes. The composition of groundwater varies in terms of chemistry and microbial activity in different locations. In this study, groundwater from the three repository areas was analyzed in respect to chemistry and microbial community. Corrosion tendency of three steel grades, carbon steel AISI/SAE 1005 and stainless steels AISI 304 and 316L, was studied in these groundwater environments using electrochemical methods. As a reference, measurements were also performed in simulated groundwater without microbes. The measurements show that corrosivity of the water and thus the steels’ performance differs depending on water origin. In addition, the groundwater differed remarkably in their chemical composition as well as abundance and diversity of microbial community between the sites. Consequently, the local environment has to be considered when evaluating the long-term evolution of disposal concepts.

Long-Exposure RGB Photography with a Fixed Stand for the Measurement of a Trajectory of a Dynamic Impact Device in Real Scale

The present manuscript proposes a novel method for the measurement of a trajectory of a falling impact hammer in the dynamic loading of conveyor belts and the determination of their impact resistance. The proposed method has been experimentally tested and the results of the measurements are presented in this manuscript. The proposed method is based on the long-exposure photography with a long-duration opened shutter of the Nikon D5000 DSLR camera. Results of the experimental research were compared with direct reference measurements performed using the L-GAGE LT3 laser distance sensor. Differences between values, obtained by the new method and by the reference measurements were up to ±3 mm. The standard deviation identified in all the experiments was 1 mm.

Validation of the complex for daily monitoring of ECG and blood pressure "Medicom-Combi" for blood pressure measurement in medical institutions in the general population (according to the Universal standard AAMi / ESH / ISO UNIVERSAL)

Purpose. To assess the accuracy of blood pressure measurement by oscillometric and auscultatory methods using the complex for daily monitoring of ECG and blood pressure «Medicom-Combi» in accordance with the criteria outlined in the Universal Standard AAMI/SH/ISO (ISO 81060-2:2018) for children and adults.Materials and methods. The study involved 90 patients (average age -33.8 ± 26.7 years) of the cardiological profile of the City Clinical Hospital No. 13 DZM, Children’s City Clinical Hospital No. 9 named after G. N. Speransky, as well as medical personnel, of which 85 were included in the analysis. For each participant, 3 pairs of valid measurements were obtained (reference-test, 255 pairs of measurements in total). Reference measurements were carried out by two experts, independently of each other, using the auscultatory method. Test measurements were read from the complex by a third expert.Results. According to validation criterion 1, the mean ± standard deviation of differences between test and reference measurements was 0.1 ± 6.0/1.7 ± 5.8 mm Hg for SBP/DBP by the oscillometric method and 0.0 ± 6.5/1.3 ± 6.6 mm Hg for SBP/DBP by the auscultatory method. According to validation criterion 2, the standard deviation of the average difference between the BP values of the same patient according to the results of test and reference measurements did not exceed 6.95/6.73 for SBP/DBP by the oscillometric method and 6.95/6.82 mm Hg for SBP/DBP by the auscultatory method.Conclusion. The complex for daily monitoring of ECG and blood pressure «Medicom-Combi» meets the requirements of the Universal Standard AAMI/ESH/ISO in terms of measurement accuracy for devices intended for use among children and adults when assessing blood pressure by oscillometric and auscultatory methods.