scholarly journals MULTI-TEMPORAL ASSESSMENT OF LYCHEE TREE CROP STRUCTURE USING MULTI-SPECTRAL RPAS IMAGERY

2017 ◽  
Vol XLII-2/W6 ◽  
pp. 165-170 ◽  
Author(s):  
K. Johansen ◽  
T. Raharjo
Keyword(s):  
Structural Parameters ◽  
Tree Structure ◽  
Flying Height ◽  
Fleshy Fruit ◽  
Tree Crown ◽  
Average Decrease ◽  
Crown Width ◽  
Before And After ◽  
Consistent Manner ◽  
Aircraft System

The lychee tree is native to China and produce small fleshy fruit up to 5 cm in diameter. Lychee production in Australia is worth > $20 million annually. Pruning of trees encourages new growth, has a positive effect on fruiting of lychee, makes fruit-picking easier, and may increase yield, as it increases light interception and tree crown surface area. The objective of this research was to assess changes in tree structure, i.e. tree crown circumference, width, height and Plant Projective Cover (PPC) using multi-spectral Remotely Piloted Aircraft System (RPAS) imagery collected before and after pruning of a lychee plantation. A secondary objective was to assess any variations in the results as a function of various flying heights (30, 50 and 70 m). Pre- and post-pruning results showed significant differences in all measured tree structural parameters, including an average decrease in: tree crown circumference of 1.94 m; tree crown width of 0.57 m; tree crown height of 0.62 m; and PPC of 14.8 %. The different flying heights produced similar measurements of tree crown width and PPC, whereas tree crown circumference and height measurements decreased with increasing flying height. These results show that multi-spectral RPAS imagery can provide a suitable means of assessing pruning efforts undertaken by contractors based on changes in tree structure of lychee plantations and that it is important to collect imagery in a consistent manner, as varying flying heights may cause changes to tree structural measurements.

scholarly journals Using Multi-Spectral UAV Imagery to Extract Tree Crop Structural Properties and Assess Pruning Effects

2018 ◽  
Author(s):  
Kasper Johansen ◽  
Tri Raharjo ◽  
Matthew F. McCabe
Keyword(s):  
Structural Parameters ◽  
Tree Structure ◽  
Flying Height ◽  
Tree Crown ◽  
Average Decrease ◽  
Crown Width ◽  
Before And After ◽  
The Impact ◽  
Positive Effect ◽  
Insight Into

Unmanned aerial vehicles (UAV) provide an unprecedented capacity to monitor the development and dynamics of tree growth and structure through time. It is generally thought that the pruning of tree crops encourages new growth, has a positive effect on fruiting, makes fruit-picking easier, and may increase yield, as it increases light interception and tree crown surface area. To establish the response of pruning in an orchard of lychee trees, an assessment of changes in tree structure, i.e. tree crown perimeter, width, height, area and Plant Projective Cover (PPC), was undertaken using multi-spectral UAV imagery collected before and after a pruning event. While tree crown perimeter, width and area could be derived directly from the delineated tree crowns, height was estimated from a produced canopy height model and PPC was most accurately predicted based on the NIR band. Pre- and post-pruning results showed significant differences in all measured tree structural parameters, including an average decrease in tree crown perimeter of 1.94 m, tree crown width of 0.57 m, tree crown height of 0.62 m, tree crown area of 3.5 m2, and PPC of 14.8%. In order to provide guidance on data collection protocols for orchard management, the impact of flying height variations was also examined, offering some insight into the influence of scale and the scalability of this UAV based approach for larger orchards. The different flying heights (i.e. 30, 50 and 70 m) produced similar measurements of tree crown width and PPC, while tree crown perimeter, area and height measurements decreased with increasing flying height. Overall, these results illustrate that routine collection of multi-spectral UAV imagery can provide a means of assessing pruning effects on changes in tree structure in commercial orchards, and highlight the importance of collecting imagery with consistent flight configurations, as varying flying heights may cause changes to tree structural measurements.

scholarly journals Dynamic variations in salinity and potassium grade of a potassium-rich brine deposit in Lop Nor basin, China

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lichun Ma ◽  
Kai Wang ◽  
Yu Zhang ◽  
Qingfeng Tang ◽  
Hui Yan
Keyword(s):  
Large Scale ◽  
Sustainable Use ◽  
Potassium Sulfate ◽  
Middle Pleistocene ◽  
Underground Brine ◽  
Average Decrease ◽  
Rational Development ◽  
Mining History ◽  
Before And After ◽  
Lop Nor

AbstractThe Quaternary Lop Nor playa is the largest production base of potassium sulfate in the world. It has a mining history of more than 10 years, and its share in the Chinese potassium sulfate market is about 50% to-date. In this basin, the high-salinity potassium-rich brines are mainly contained in Middle Pleistocene–Holocene glauberite strata. Based on the monitoring of the underground brine table and geochemical analysis, this study reveals variations in the underground brine table and potassium-bearing grade before and after large-scale mining in the Lop Nor potash deposit. The results showed that the underground brine table and potassium sulfate grade decreased by varying degrees over sub-mineral areas after large-scale mining. The underground brine table declined by 8.5 m, on average, in the Luobei depression, by 6.4 m in the Tenglong platform and by 1.9 m in the Xinqing platform. However, the potassium-bearing grade showed the different trend. The Tenglong platform had the largest decline with average decreases in layers W1, W2 and W3 of 18.2%, 13.0% and 24.8%, respectively. In the Xinqing platform, the average decrease in layersW2 and W3 were 17.4% and 16.0% respectively. The Luobei depression decreases were relatively small (W1, W2 and W3 decreased 4.3%, 4.2% and 3.1%, respectively). This research provides a theoretical basis for the rational development and sustainable use of the potassium-rich brines in the Lop Nor basin.

scholarly journals Vision-Based Structural FE Model Updating Using Genetic Algorithm

2021 ◽  
Vol 11 (4) ◽  
pp. 1622
Author(s):  
Gun Park ◽  
Ki-Nam Hong ◽  
Hyungchul Yoon
Keyword(s):  
Genetic Algorithm ◽  
Model Updating ◽  
Structural Parameters ◽  
Fe Model ◽  
Structural Members ◽  
Stiffness Reduction ◽  
Before And After ◽  
Scale Test ◽  
Fe Model Updating ◽  
Story Building

Structural members can be damaged from earthquakes or deterioration. The finite element (FE) model of a structure should be updated to reflect the damage conditions. If the stiffness reduction is ignored, the analysis results will be unreliable. Conventional FE model updating techniques measure the structure response with accelerometers to update the FE model. However, accelerometers can measure the response only where the sensor is installed. This paper introduces a new computer-vision based method for structural FE model updating using genetic algorithm. The system measures the displacement of the structure using seven different object tracking algorithms, and optimizes the structural parameters using genetic algorithm. To validate the performance, a lab-scale test with a three-story building was conducted. The displacement of each story of the building was measured before and after reducing the stiffness of one column. Genetic algorithm automatically optimized the non-damaged state of the FE model to the damaged state. The proposed method successfully updated the FE model to the damaged state. The proposed method is expected to reduce the time and cost of FE model updating.

Over-the-row harvester damage evaluation in super-high-density olive orchard by on-board sensing techniques

2017 ◽  
Vol 8 (2) ◽  
pp. 487-491 ◽  
Author(s):  
J. Martinez-Guanter ◽  
M. Garrido-Izard ◽  
J. Agüera ◽  
C. Valero ◽  
M. Pérez-Ruiz
Keyword(s):  
Structural Damage ◽  
Image Data ◽  
High Density ◽  
Tree Structure ◽  
Light Detection And Ranging ◽  
Olive Grove ◽  
Damage Evaluation ◽  
Olive Fruit ◽  
Before And After ◽  
Extra Stress

New Super-High-Density (SHD) olive orchards designed for mechanical harvesting are increasing very rapidly in Spain. Most studies have focused in effectively removing the olive fruit, however the machine needs to put significant amount of energy on the canopy that could result in structural damage or extra stress on the trees. During harvest, a series of 3-axis accelerometers were installed on the tree structure in order to register vibration patterns. A LiDAR (Light Detection and Ranging) and a camera sensing device were also mounted on a tractor. Before and after harvest measurements showed significant differences in the LiDAR and image data. A fast estimate of the damage produced by an over-the-row harvester with contactless sensing could be useful information for adjusting the machine parameters in each olive grove automatically in the future.

The Effect of Tongue-Tie Release on Speech Articulation and Intelligibility

2021 ◽  
pp. 014556132110640
Author(s):  
Jonathan Melong ◽  
Michael Bezuhly ◽  
Paul Hong
Keyword(s):  
Speech Intelligibility ◽  
Developmentally Appropriate ◽  
Speech Sound ◽  
Speech Errors ◽  
Speech Articulation ◽  
Speech Language Pathologist ◽  
Audio Recordings ◽  
Before And After ◽  
Consistent Manner ◽  
Age Appropriate

Objective The relationship between ankyloglossia and speech is controversial. The objective of this study was to determine the effect of tongue-tie release on speech articulation and intelligibility. Methods A prospective cohort study was conducted. Pediatric patients (>2 years of age) being referred for speech concerns due to ankyloglossia were assessed by a pediatric otolaryngologist, and speech articulation was formally assessed by a speech language pathologist using the Goldman-Fristoe Test of Articulation 2 (GFTA-2). Patients then underwent a tongue-tie release procedure in clinic. After 1 month, speech articulation was reassessed with GFTA-2. Audio-recordings of sessions were evaluated by independent reviewers to assess speech intelligibility before and after tongue-tie release. Results Twenty-five participants were included (mean age 3.7 years; 20 boys). The most common speech errors identified were phonological substitutions (80%) and gliding errors (56%). Seven children (28%) had abnormal lingual-alveolar and interdental sounds. Most speech sound errors (87.9%) were age/developmentally appropriate. GFTA-2 standard scores before and after tongue-tie release were 85.61 (SD 9.75) and 87.54 (SD 10.21), respectively, (P=.5). Mean intelligibility scores before and after tongue-tie release were 3.15 (SD .22) and 3.21 (SD .31), respectively, (P=.43). Conclusion The majority of children being referred for speech concerns thought to be due to ankyloglossia had age-appropriate speech errors at presentation. Ankyloglossia was not associated with isolated tongue mobility related speech articulation errors in a consistent manner, and there was no benefit of tongue-tie release in improving speech articulation or intelligibility.

Management of posaconazole-induced pseudohyperaldosteronism

2020 ◽  
Vol 75 (12) ◽  
pp. 3688-3693
Author(s):  
Matthew R Davis ◽  
Minh-Vu H Nguyen ◽  
Thomas J Gintjee ◽  
Alex Odermatt ◽  
Brian Y Young ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Dose Reduction ◽  
Serum Potassium ◽  
Continuous Monitoring ◽  
Therapeutic Interventions ◽  
Serum Concentrations ◽  
Average Decrease ◽  
Before And After ◽  
Repeat Assessment

Abstract Background Posaconazole-induced pseudohyperaldosteronism (PIPH) has been associated with elevated posaconazole serum concentrations. Clinicians are faced with the difficult task of managing patients with PIPH while maintaining the efficacy of antifungal therapy. Commonly, modifications to posaconazole therapy are utilized in managing PIPH, including dosage reduction of posaconazole or switch to an alternative antifungal. Objectives To characterize the management of patients diagnosed with PIPH and their response to various therapeutic interventions. Methods We retrospectively reviewed 20 consecutive adult patients diagnosed with PIPH. Patient data collected included blood pressure, electrolytes, endocrine laboratory values and posaconazole serum concentrations collected before and after therapeutic intervention. Results Of 20 patients included, 17 patients (85%) underwent therapeutic modification, with posaconazole dose reduction (n = 11) as the most common change. Other modifications included discontinuation (n = 3), switch to an alternative antifungal (n = 2) and addition of spironolactone (n = 1). Clinical improvement (decrease in systolic blood pressure and increase in serum potassium) was observed in 9 of 17 patients (52.9%). An average decrease in systolic blood pressure of 7.1 mmHg and increase in serum potassium of 0.22 mmol/L was observed following therapeutic modification. Conclusions We report our experience with PIPH management, for which there is no universally effective strategy. We utilized a stepwise approach for management, starting with posaconazole dose reduction and repeat assessment of clinical and laboratory parameters. If resolution of PIPH is not achieved, an alternative triazole antifungal or the addition of an aldosterone antagonist are additional potential interventions. It is possible for PIPH to persist after therapeutic modification despite these interventions. Thus, early diagnosis and continuous monitoring is warranted.

The Effect of Artificial Portocaval Anastomosis or Splenectomy on Hepatic and Portal Haemodynamics in Cirrhotics

1969 ◽  
Vol 08 (03) ◽  
pp. 232-241
Author(s):  
J. Vosmík ◽  
V. Bláha
Keyword(s):  
Blood Flow ◽  
Liver Cirrhosis ◽  
Portal Hypertension ◽  
Liver Blood Flow ◽  
Severe Liver ◽  
Portocaval Anastomosis ◽  
Average Decrease ◽  
Modified Method ◽  
Portosystemic Shunts ◽  
Before And After

SummaryUsing their own modified method the authors simultaneously examined the blood clearances of 198Au colloid and 131I-Rose Bengal and determined the ratio1. in a group of 11 patients with severe liver cirrhosis, portal hypertension and portosystemic shunts, both before and after artificial portocaval anastomosis, and2. in two patients with thrombosis v. lienalis, excessive splenomegaly and extensive portosystemic shunts before and after splenectomy. Ad 1. In 6 patients 55%) a reduction of the effective liver blood flow occured due to the artificial portosystemic anastomosis; the average decrease was ~ 20%. In 7 patients a significant enlargement of the total splenosystemic flow was observed as a result of the artificial communication.Ad 2. In both patients an increase of the effective liver blood flow occured after splenectomy. The minimal preoperative splenosystemic flow was ~ 0.152 and ~ 0.089 of the circulating blood per minute (expressed by means of kAu).The authors discuss the significance of the kAu and kBR values as well as that of the ratio for the estimation of changes in hepatic and portal haemodynamics.

Patient Transport and Brain Oxygen in Comatose Patients

Neurosurgery ◽  
2010 ◽  
Vol 66 (5) ◽  
pp. 925-932 ◽  
Author(s):  
Edward W. Swanson ◽  
Justin Mascitelli ◽  
Michael Stiefel ◽  
Eileen MacMurtrie ◽  
Joshua Levine ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Intensive Care Unit ◽  
Intensive Care ◽  
Lung Function ◽  
Parameter Estimate ◽  
Brain Hypoxia ◽  
Average Decrease ◽  
Brain Oxygen ◽  
Before And After ◽  
Head Computed Tomography

Abstract OBJECTIVE Transport of critically ill intensive care unit patients may be hazardous. We examined whether brain oxygen (brain tissue oxygen partial pressure [PbtO2]) is influenced by transport to and from a follow-up head computed tomography (transport head computed tomography [tHCT]) scan. METHODS Forty-five patients (24 men, 21 women; Glasgow Coma Scale score ≤8; mean age, 47.3 ± 19.0 years) who had a traumatic brain injury (n = 26) or subarachnoid hemorrhage (n = 19) were retrospectively identified from a prospective observational cohort of PbtO2 monitoring in a neurosurgical intensive care unit at a university-based level I trauma center. PbtO2, intracranial pressure, and cerebral perfusion pressure were monitored continuously and compared during the 3 hours before and after 100 tHCT scans. RESULTS The mean PbtO2 before and after the tHCT scans for all 100 scans was 37.9 ± 19.8 mm Hg and 33.9 ± 17.2 mm Hg, respectively (P = .0001). A decrease in PbtO2 (>5%) occurred after 54 tHCTs (54%) and in 36 patients (80%). In instances in which a decrease occurred, the average decrease in mean, minimum, and maximum PbtO2 was 23.6%, 29%, and 18.1%, respectively. This decrease was greater when PbtO2 was compromised (<25 mm Hg) before tHCT. An episode of brain hypoxia (<15 mm Hg) was identified in the 3 hours before tHCT in 9 and after tHCT in 19 instances. On average, an episode of brain hypoxia was 46.6 ± 16.0 (standard error) minutes longer after tHCT than before tHCT (P = .008). Multivariate analysis suggests that changes in lung function (PaO2/fraction of inspired oxygen [FiO2] ratio) may account for the reduced PbtO2 after tHCT (parameter estimate 0.45, 95% confidence interval: 0.024–0.871; P = .04). CONCLUSION These data suggest that transport to and from the intensive care unit may adversely affect PbtO2. This deleterious effect is greater when PbtO2 is already compromised and may be associated with lung function.

scholarly journals The Evolutionary Characteristics of Reservoir Microstructure under Long-Term Waterflooding Development and Its Fractal Description

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Fengjiao Wang ◽  
Xu Wang ◽  
Yikun Liu ◽  
Qingjun Deng ◽  
Jianjun Xu ◽  
...  
Keyword(s):  
Pore Structure ◽  
Physical Simulation ◽  
Structural Parameters ◽  
Fractal Theory ◽  
Evolution Model ◽  
Structure Evolution ◽  
Before And After ◽  
Water Cut ◽  
The Relationship

Generally, long-term waterflooding development often leads to the change of reservoir pore and clay mineral composition, which results in the change of permeability and wettability. In order to explore the relationship between core micropore structure and water cut, based on physical simulation experiments and fractal theory, we proposed a fractal evolutionary model to describe the evolution characteristics of microstructure of long-term water driving reservoirs. In this paper, core pore structure by SEM was first conducted to analyze the change of core pore structure before and after waterflooding under the conditions of magnification of 200 times, 800 times, and 2000 times, respectively. Then, conventional and constant rate mercury injection tests were combined to perform the comparative analysis of core structural parameters before and after waterflooding. Finally, a micropore-throat structure evolution model of core was established. Research shows that the connectivity of larger pores becomes better after long-term water driving, the degree of heterogeneity weakens, and the micro heterogeneity of small pores becomes stronger and stronger. The throat characteristics change in a complex manner, the radius tends to increase, and the sorting becomes better, while the connectivity of small throat changes complex. In general, the heterogeneity of throat increases with the time of water injection in reservoirs with low porosity and permeability. On the basis of fractal theory and variation characteristics of rock pore structure in water driving reservoirs, we have established a micropore-throat structure evolution model of core pore-throat characteristics. This fractal evolution model quantitatively characterized the complexity and evolution law of pore structure and clarified the relationship between fractal dimension of core pore structure and water cut under different stages of water driving.

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