scholarly journals Terrestrial Structure from Motion Photogrammetry for Deriving Forest Inventory Data

2019 ◽  
Vol 11 (8) ◽  
pp. 950 ◽  
Author(s):  
Livia Piermattei ◽  
Wilfried Karel ◽  
Di Wang ◽  
Martin Wieser ◽  
Martin Mokroš ◽  
...  
Keyword(s):  
Structure From Motion ◽  
Forest Inventory ◽  
Point Clouds ◽  
Alternative Methods ◽  
Acquisition Time ◽  
Image Capture ◽  
Wide Range ◽  
Capture Method ◽  
The Mean

The measurements of tree attributes required for forest monitoring and management planning, e.g., National Forest Inventories, are derived by rather time-consuming field measurements on sample plots, using calipers and measurement tapes. Therefore, forest managers and researchers are looking for alternative methods. Currently, terrestrial laser scanning (TLS) is the remote sensing method that provides the most accurate point clouds at the plot-level to derive these attributes from. However, the demand for even more efficient and effective solutions triggers further developments to lower the acquisition time, costs, and the expertise needed to acquire and process 3D point clouds, while maintaining the quality of extracted tree parameters. In this context, photogrammetry is considered a potential solution. Despite a variety of studies, much uncertainty still exists about the quality of photogrammetry-based methods for deriving plot-level forest attributes in natural forests. Therefore, the overall goal of this study is to evaluate the competitiveness of terrestrial photogrammetry based on structure from motion (SfM) and dense image matching for deriving tree positions, diameters at breast height (DBHs), and stem curves of forest plots by means of a consumer grade camera. We define an image capture method and we assess the accuracy of the photogrammetric results on four forest plots located in Austria and Slovakia, two in each country, selected to cover a wide range of conditions such as terrain slope, undergrowth vegetation, and tree density, age, and species. For each forest plot, the reference data of the forest parameters were obtained by conducting field surveys and TLS measurements almost simultaneously with the photogrammetric acquisitions. The TLS data were also used to estimate the accuracy of the photogrammetric ground height, which is a necessary product to derive DBHs and tree heights. For each plot, we automatically derived tree counts, tree positions, DBHs, and part of the stem curve from both TLS and SfM using a software developed at TU Wien (Forest Analysis and Inventory Tool, FAIT), and the results were compared. The images were oriented with errors of a few millimetres only, according to checkpoint residuals. The automatic tree detection rate for the SfM reconstruction ranges between 65% and 98%, where the missing trees have average DBHs of less than 12 cm. For each plot, the mean error of SfM and TLS DBH estimates is −1.13 cm and −0.77 cm with respect to the caliper measurements. The resulting stem curves show that the mean differences between SfM and TLS stem diameters is at maximum −2.45 cm up to 3 m above ground, which increases to almost +4 cm for higher elevations. This study shows that with the adopted image capture method, terrestrial SfM photogrammetry, is an accurate solution to support forest inventory for estimating the number of trees and their location, the DBHs and stem curve up to 3 m above ground.

Hidradenitis suppurativa: Wie die Partner von Betroffenen psychosozial beeinträchtigt werden

2021 ◽  
pp. 1-3
Author(s):  
Uwe Gieler
Keyword(s):  
Disease Severity ◽  
Social Life ◽  
Hidradenitis Suppurativa ◽  
Life Quality ◽  
Psychosocial Burden ◽  
Wide Range ◽  
The Family ◽  
The Mean ◽  
Moderate Effect

<b>Background</b>: Hidradenitis suppurativa is a debilitating disease related to a great psychosocial burden in affected patients and subsequently also people around them. Patients’ partners as caregivers may indirectly experience wide range of devastating effects of the disease on their emotional and social life. <b>Objective:</b> The purpose of this study was to determine the QoL impairment in HS patients’ partners and to identify its aspects that are affected the most. Correlation between QoL burden and disease severity, duration, sex, age and smoking was also assessed. <b>Methods:</b> A total of 50 HS sufferers were assessed according to disease severity and their partners’ QoL was determined using the Family Dermatology Life Quality Index questionnaire. <b>Results:</b> The mean FDLQI for patients’ partners was 8.7 ± 6.8 points, indicating generally a moderate effect of HS on their life. Quality of partners’ life correlated significantly with disease severity but no correlation was found according to other factors. <b>Conclusion:</b> Hidradenitis suppurativa is a highly psychologically devastating disease not only for patients but also for their partners. It occurred to diminish partners’ QoL mostly by increasing daily expenditure but also other problems were often reported. Clinicians should be aware of these psychosocial implications, in order to provide optimal therapy of HS affected families by a multidisciplinary specialized management addressing both, patients and their cohabitants simultaneously.

scholarly journals QUALITY PREDICTION OF DENSE POINTS GENERATED BY STRUCTURE FROM MOTION FOR HIGH-QUALITY AND EFFICIENT AS-IS MODEL RECONSTRUCTION

2019 ◽  
Vol XLII-2/W13 ◽  
pp. 95-101
Author(s):  
R. Moritani ◽  
S. Kanai ◽  
H. Date ◽  
Y. Niina ◽  
R. Honma
Keyword(s):  
Structure From Motion ◽  
Point Clouds ◽  
Quality Prediction ◽  
Construction Site ◽  
Model Reconstruction ◽  
High Quality ◽  
Bridge Column ◽  
Dense Point ◽  
Selection Of

<p><strong>Abstract.</strong> In this paper, we introduce a method for predicting the quality of dense points and selecting low-quality regions on the points generated by the structure from motion (SfM) and multi-view stereo (MVS) pipeline to realize high-quality and efficient as-is model reconstruction, using only results from the former: sparse point clouds and camera poses. The method was shown to estimate the quality of the final dense points as the quality predictor on an approximated model obtained from SfM only, without requiring the time-consuming MVS process. Moreover, the predictors can be used for selection of low-quality regions on the approximated model to estimate the next-best optimum camera poses which could improve quality. Furthermore, the method was applied to the prediction of dense point quality generated from the image sets of a concrete bridge column and construction site, and the prediction was validated in a time much shorter than using MVS. Finally, we discussed the correlation between the predictors and the final dense point quality.</p>

Piezoelectric bone conduction hearing implant Osia® - audiological and quality of life benefits

2021 ◽  
Vol 75 (4) ◽  
pp. 1-5
Author(s):  
Joanna Marszał ◽  
Renata Gibasiewicz ◽  
Magdalena Błaszczyk ◽  
Maria Gawlowska ◽  
Wojciech Gawęcki
Keyword(s):  
Quality Of Life ◽  
Hearing Loss ◽  
Hearing Aids ◽  
Bone Conduction ◽  
Speech Understanding ◽  
Mixed Hearing Loss ◽  
Wide Range ◽  
The Mean ◽  
Bone Conduction Hearing

Introduction: Nowadays, there are many options to treat hearing-impaired patients: tympanoplastic surgery, hearing aids and a wide range of implantable devices. Objective: The aim of this study is to present the mid-term audiological and quality of life benefits after the implantation of the Osia®, a new active piezoelectric bone conduction hearing implant. Material and methods: The state of the tissues in implanted area, as well as audiological and quality of life results were analyzed six, nine and twelve months after implantation in a group of four adult patients with bilateral mixed hearing loss. Results: In all the cases, no postoperative complications were found. One year after surgery the mean audiological gain in FF PTA4 (pure tone average for 0.5, 1, 2, and 4 kHz) was 52.2±3.5 dB in comparison to the unaided situation, the mean speech understanding with Osia® in quiet was 90±8.2% for 50dB SPL, 98.8±2.5% for 65dB SPL and 100±0% for 80dB SPL, and mean speech understanding with Osia® in noise was 37.5%±23.6 for 50dB SPL, 93.8±4.8% for 65dB SPL and 98.8±2.5% for 80dB SPL. There was also an evident improvement in the quality of hearing as well as in the quality of life, measured by the APHAB (Abbreviated Profile of Hearing Aid Benefit) and the SSQ (Speech, Spatial and Qualities of Hearing Scale). Conclusions: The Osia® is an effective treatment option for patients with bilateral mixed hearing loss. The mid-term audiological and quality of life results are excellent, but further observations including bigger groups of patients and a longer follow-up are required.

Evaluation of the Anti-Factor Xa Chromogenic Assay for Measuring Rivaroxaban Plasma Concentrations Using Calibrators and Controls

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3330-3330 ◽  
Author(s):  
Meyer Michel Samama ◽  
Genevieve Contant ◽  
Theodore E Spiro ◽  
Elisabeth Perzborn ◽  
Céline Guinet ◽  
...  
Keyword(s):  
Human Plasma ◽  
Calibration Curve ◽  
Plasma Concentrations ◽  
Control Sample ◽  
Factor Xa ◽  
Alternative Methods ◽  
Preliminary Results ◽  
Chromogenic Assay ◽  
Wide Range ◽  
The Mean

Abstract Abstract 3330 Background: Rivaroxaban is an oral, direct Factor Xa inhibitor in an advanced stage of clinical development for the prevention and treatment of thromboembolic disorders. It inhibits Factor Xa activity without requiring cofactors (such as antithrombin) and has been found to have predictable pharmacokinetics and pharmacodynamics in humans. Routine coagulation monitoring is not required, but a quantitative determination of rivaroxaban concentrations might be useful in some cases, such as severe overdose or to measure compliance. Although the prothrombin time assay may be of assistance for the assessment of peak rivaroxaban plasma concentrations using calibrators and controls as previously shown, alternative methods such as the anti-Factor Xa chromogenic assays may allow the measurement of a wider rivaroxaban plasma concentration range. Methods: A multicenter study was initiated to evaluate the suitability of the anti-Factor Xa chromogenic assay for the measurement of rivaroxaban plasma concentrations (ng/mL) using rivaroxaban calibrators and controls, and to assess the inter-laboratory precision of the measurement. A total of 25 centers were provided with sets of rivaroxaban calibrators (0, 41, 209, and 422 ng/mL) and a set of rivaroxaban pooled human plasma controls (20, 199, and 662 ng/mL). The concentrations of the human plasma controls were unknown to the participating laboratories. The evaluation was carried out over 2 consecutive weeks (10 days) by each laboratory using its own anti-Factor Xa reagents as well as 1 provided centrally (modified STA® Rotachrom, Diagnostica Stago, Asnières-sur-Seine, France). A calibration curve was produced each day and the day-to-day precision was evaluated by testing in duplicate 3 human plasma controls. The plasma control sample was diluted (1:3 dilution) and re-tested if the measured level was above the highest concentration of the calibration curve. Results: Preliminary results from 8 centers showed that the mean rivaroxaban concentrations obtained were 21, 199, 549, and 708 ng/mL when using the modified STA Rotachrom method, or 19, 200, 556, and 676 ng/mL when using the local anti-Factor Xa reagents for the human plasma controls (19, 160, and 643 [undiluted and diluted samples] ng/mL, respectively). The mean coefficients of variation were 17.7%, 4.6%, 1.9%, and 8.9%, respectively, when using the modified STA Rotachrom method, or 33.7%, 4.7%, 2.2%, and 7.7%, respectively, when using the local anti-Factor Xa reagents. Conclusions: The preliminary results of this multicenter field trial suggest that the anti-Factor Xa chromogenic method, using rivaroxaban calibrators and controls, is suitable for measuring a wide range of rivaroxaban plasma concentrations. Disclosures: Samama: Bayer Healthcare: Consultancy. Spiro:Bayer Healthcare Pharmaceuticals Inc.: Employment. Perzborn:Bayer Schering Pharma AG: Employment.

scholarly journals INDOOR MAPPING OF A COMPLEX CULTURAL HERITAGE SCENE USING TLS AND HMLS LASER SCANNING

2021 ◽  
Vol XLIII-B2-2021 ◽  
pp. 605-612
Author(s):  
V. E. Oniga ◽  
A. I. Breaban ◽  
E. I. Alexe ◽  
C. Văsii
Keyword(s):  
Standard Deviation ◽  
Cultural Heritage ◽  
Long Range ◽  
Interior Design ◽  
Point Cloud ◽  
Laser Scanning ◽  
Laser Scanner ◽  
Point Clouds ◽  
Acquisition Time ◽  
Wide Range

Abstract. Indoor mapping and modelling is an important research subject with application in a wide range of domains including interior design, real estate, cultural heritage conservation and restoration. There are multiple sensors applicable for 3D indoor modelling, but the laser scanning technique is frequently used because of the acquisition time, detailed information and accuracy. In this paper, the efficiency of the Maptek I-Site 8820 terrestrial scanner, which is a long-range laser scanner and the accuracy of a HMLS point cloud acquired with a mobile scanner, namely GeoSlam Zeb Horizon were tested for indoor mapping. Aula Magna “Carmen Silva” of the “Gheorghe Asachi” Technical University of Iasi is studied in the current paper since the auditorium interior creates a distinct environment that combines complex geometric structures with architectural lighting and for preserving its great cultural value, the monument has a national historical significance. The registration process of the TLS point clouds was done using two methods: a semi-automatic one with artificial targets and a completely automatic one, based on Iterative Closest Point (ICP) algorithm. The resulted TLS point cloud was analysed in relation to the HMLS point cloud by computing the M3C2 (Multiscale Model to Model Cloud Comparison), obtaining a standard deviation of 2.1 cm and by investigating the Hausdorff distances from which resulted a standard deviation (σ) of 1.6 cm. Cross-sections have been extracted from the HMLS and TLS point clouds and after comparing the sections, 80% of the sigma values are less or equal to 1 cm. The results show high potential of using HMLS and also a long-range laser scanner for 3D modelling of complex scenes, the occlusion effect in the case of TLS being only 5% of the scanned area.

scholarly journals Measurement of Forest Inventory Parameters with Apple iPad Pro and Integrated LiDAR Technology

2021 ◽  
Vol 13 (16) ◽  
pp. 3129
Author(s):  
Christoph Gollob ◽  
Tim Ritter ◽  
Ralf Kraßnitzer ◽  
Andreas Tockner ◽  
Arne Nothdurft
Keyword(s):  
Data Acquisition ◽  
Forest Inventory ◽  
Laser Scanning ◽  
Point Clouds ◽  
Acquisition Time ◽  
Ecosystem Monitoring ◽  
Individual Tree ◽  
3D Point Clouds ◽  
Apple Ipad ◽  
Laser Scanners

The estimation of single tree and complete stand information is one of the central tasks of forest inventory. In recent years, automatic algorithms have been successfully developed for the detection and measurement of trees with laser scanning technology. Nevertheless, most of the forest inventories are nowadays carried out with manual tree measurements using traditional instruments. This is due to the high investment costs for modern laser scanner equipment and, in particular, the time-consuming and incomplete nature of data acquisition with stationary terrestrial laser scanners. Traditionally, forest inventory data are collected through manual surveys with calipers or tapes. Practically, this is both labor and time-consuming. In 2020, Apple implemented a Light Detection and Ranging (LiDAR) sensor in the new Apple iPad Pro (4th Gen) and iPhone Pro 12. Since then, access to LiDAR-generated 3D point clouds has become possible with consumer-level devices. In this study, an Apple iPad Pro was tested to produce 3D point clouds, and its performance was compared with a personal laser scanning (PLS) approach to estimate individual tree parameters in different forest types and structures. Reference data were obtained by traditional measurements on 21 circular forest inventory sample plots with a 7 m radius. The tree mapping with the iPad showed a detection rate of 97.3% compared to 99.5% with the PLS scans for trees with a lower diameter at a breast height (dbh) threshold of 10 cm. The root mean square error (RMSE) of the best dbh measurement out of five different dbh modeling approaches was 3.13 cm with the iPad and 1.59 cm with PLS. The data acquisition time with the iPad was approximately 7.51 min per sample plot; this is twice as long as that with PLS but 2.5 times shorter than that with traditional forest inventory equipment. In conclusion, the proposed forest inventory with the iPad is generally feasible and achieves accurate and precise stem counts and dbh measurements with efficient labor effort compared to traditional approaches. Along with future technological developments, it is expected that other consumer-level handheld devices with integrated laser scanners will also be developed beyond the iPad, which will serve as an accurate and cost-efficient alternative solution to the approved but relatively expensive TLS and PLS systems. Such a development would be mandatory to broadly establish digital technology and fully automated routines in forest inventory practice. Finally, high-level progress is generally expected for the broader scientific community in forest ecosystem monitoring, as the collection of highly precise 3D point cloud data is no longer hindered by financial burdens.

Hemodialysis and peritoneal dialysis—health-related quality of life: systematic review plus meta-analysis

2021 ◽  
pp. bmjspcare-2021-003182
Author(s):  
Samira Raoofi ◽  
Fatemeh Pashazadeh Kan ◽  
Sima Rafiei ◽  
Zahra Hoseinipalangi ◽  
Sepide Rezaei ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Short Form ◽  
Meta Analysis ◽  
Health Condition ◽  
Factors Affecting ◽  
Sf 36 ◽  
Wide Range ◽  
Health Related ◽  
The Mean

BackgroundPatients with end-stage renal disease undergoing haemodialysis experience a variety of stressors leading to decreased level of quality of life (QoL). Thus, in this study, we aimed to review the current literature and identify factors affecting the health-related QoL (HRQoL) in these patients.MethodsA total of 147 studies were extracted from databases of Web of Science, PubMed, Scopus, Google Scholar, and Embase published between January 2000 and December 2020. Data were analysed using R software and results were reported with reference to Preferred Reporting Items for Systematic Reviews and Meta-Analyses standards.ResultsA total of 623 728 patients undergoing dialysis participated in 147 studies in which QoL was assessed by means of two valid questionnaires, including Short-Form 36 (SF-36) and Kidney Disease Quality of Life (KDQOL)-short form V.1.3. Total HRQoL score for patients undergoing dialysis measured by KDQOL was 64.25 (95% CI 55.67 to 72.82). Based on SF-36, the mean score of mental health items was higher than the mean score of physical health condition. Furthermore, meta-regression based on the geographical place of residence revealed that the highest QoL in patients was observed in Japan, 66.96 (95% CI 63.65 to 70.28) and Brazil, 58.03 (95% CI 53.45 to 62.6).ConclusionStudies conducted on HRQoL among patients undergoing dialysis recommend useful strategies to clinicians, letting them assess patients’ QoL in terms of a wide range of physical, mental and environmental aspects.

scholarly journals Are gluten-free foods healthier than non-gluten-free foods? An evaluation of supermarket products in Australia

2015 ◽  
Vol 114 (3) ◽  
pp. 448-454 ◽  
Author(s):  
Jason H. Y. Wu ◽  
Bruce Neal ◽  
Helen Trevena ◽  
Michelle Crino ◽  
Wendy Stuart-Smith ◽  
...  
Keyword(s):  
Food Products ◽  
Gluten Free ◽  
Food Groups ◽  
Product Packaging ◽  
Processed Meats ◽  
Optimal Score ◽  
Wide Range ◽  
Secondary Analyses ◽  
The Mean

Despite tremendous growth in the consumption of gluten-free (GF) foods, there is a lack of evaluation of their nutritional profile and how they compare with non-GF foods. The present study evaluated the nutritional quality of GF and non-GF foods in core food groups, and a wide range of discretionary products in Australian supermarkets. Nutritional information on the Nutrition Information Panel was systematically obtained from all packaged foods at four large supermarkets in Sydney, Australia in 2013. Food products were classified as GF if a GF declaration appeared anywhere on the product packaging, or non-GF if they contained gluten, wheat, rye, triticale, barley, oats or spelt. The primary outcome was the ‘Health Star Rating’ (HSR: lowest score 0·5; optimal score 5), a nutrient profiling scheme endorsed by the Australian Government. Differences in the content of individual nutrients were explored in secondary analyses. A total of 3213 food products across ten food categories were included. On average, GF plain dry pasta scored nearly 0·5 stars less (P< 0·001) compared with non-GF products; however, there were no significant differences in the mean HSR for breads or ready-to-eat breakfast cereals (P≥ 0·42 for both). Relative to non-GF foods, GF products had consistently lower average protein content across all the three core food groups, in particular for pasta and breads (52 and 32 % less, P< 0·001 for both). A substantial proportion of foods in discretionary categories carried GF labels (e.g. 87 % of processed meats), and the average HSR of GF discretionary foods were not systematically superior to those of non-GF products. The consumption of GF products is unlikely to confer health benefits, unless there is clear evidence of gluten intolerance.

scholarly journals Assessing the Ability of Image Based Point Clouds Captured from a UAV to Measure the Terrain in the Presence of Canopy Cover

Forests ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 284 ◽  
Author(s):  
Luke Wallace ◽  
Chris Bellman ◽  
Bryan Hally ◽  
Jaime Hernandez ◽  
Simon Jones ◽  
...  
Keyword(s):  
Ground Surface ◽  
Canopy Cover ◽  
Weather Conditions ◽  
Point Clouds ◽  
Unmanned Aerial Systems ◽  
Image Capture ◽  
Terrain Model ◽  
Processing Strategies ◽  
Aerial Systems

Point clouds captured from Unmanned Aerial Systems are increasingly relied upon to provide information describing the structure of forests. The quality of the information derived from these point clouds is dependent on a range of variables, including the type and structure of the forest, weather conditions and flying parameters. A key requirement to achieve accurate estimates of height based metrics describing forest structure is a source of ground information. This study explores the availability and reliability of ground surface points available within point clouds captured in six forests of different structure (canopy cover and height), using three image capture and processing strategies, consisting of nadir, oblique and composite nadir/oblique image networks. The ground information was extracted through manual segmentation of the point clouds as well as through the use of two commonly used ground filters, LAStools lasground and the Cloth Simulation Filter. The outcomes of these strategies were assessed against ground control captured with a Total Station. Results indicate that a small increase in the number of ground points captured (between 0 and 5% of a 10 m radius plot) can be achieved through the use of a composite image network. In the case of manually identified ground points, this reduced the root mean square error (RMSE) error of the terrain model by between 1 and 11 cm, with greater reductions seen in plots with high canopy cover. The ground filters trialled were not able to exploit the extra information in the point clouds and inconsistent results in terrain RMSE were obtained across the various plots and imaging network configurations. The use of a composite network also provided greater penetration into the canopy, which is likely to improve the representation of mid-canopy elements.

scholarly journals Advances in mapping sub-canopy snow depth with unmanned aerial vehicles using structure from motion and lidar techniques

2019 ◽  
Author(s):  
Phillip Harder ◽  
John W. Pomeroy ◽  
Warren D. Helgason
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Structure From Motion ◽  
Snow Depth ◽  
Point Clouds ◽  
Airborne Lidar ◽  
Canadian Prairie ◽  
Widespread Application ◽  
Aerial Vehicles ◽  
Wide Range ◽  
Consistent Error

Abstract. Vegetation has a tremendous influence on snow processes and snowpack dynamics yet remote sensing techniques to resolve the spatial variability of sub-canopy snow depth are lacking. Unmanned Aerial Vehicles (UAV) have had recent widespread application to capture high resolution information on snow processes and are herein applied to the sub-canopy snow depth challenge. Previous demonstrations of snow depth mapping with UAV Structure from Motion (SfM) and airborne-lidar have focussed on non-vegetated surfaces or reported large errors in the presence of vegetation. In contrast, UAV-lidar systems have high-density point clouds, measure returns from a wide range of scan angles, and so have a greater likelihood of successfully sensing the sub-canopy snow depth. The effectiveness of UAV-lidar and UAV-SfM in mapping snow depth in both open and forested terrain was tested in a 2019 field campaign in the Canadian Rockies Hydrological Observatory, Alberta and at Canadian Prairie sites near Saskatoon, Saskatchewan, Canada. Only UAV-lidar could successfully measure the sub-canopy snow surface with reliable sub-canopy point coverage, and consistent error metrics (RMSE

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