optimal area
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2022 ◽  
Vol 14 (1) ◽  
Author(s):  
Paul Olszynski ◽  
Rory A. Marshall ◽  
T. Dylan Olver ◽  
Trevor Oleniuk ◽  
Cameron Auser ◽  
...  

Abstract Background While intra-arrest echocardiography can be used to guide and monitor chest compression quality, it is not currently feasible on the scene of out-of-hospital cardiac arrests. Rapid and automated sonographic localization of the heart may provide first-responders guidance to an optimal area of compression without requiring them to interpret ultrasound images. In this proof-of-concept porcine study, we sought to describe the performance of an automated ultrasound device in correctly identifying and tracing the borders of the heart in three distinct states: pre-arrest, arrest, and late arrest. Methods An automated ultrasound device (bladder scanner) was placed on the chests of 7 swine, along the left sternal border (4th–8th intercostal spaces). Scanner-generated images were recorded for each space during pre-arrest, arrest, and finally late arrest. 828 images of the LV and LV outflow tract were randomized and 150 (50/state) selected for analysis. Scanner tracings of the heart were then digitally obscured to facilitate tracing by expert reviewers who were blinded to the physiologic state. Reviewer tracings were compared to bladder scanner tracings; with concordance between these images determined via Sørensen–Dice index (SDI). Results When compared to human reviewers, the bladder scanner was able to identify and trace the borders during cardiac arrest. The bladder scanner performed best at the time of arrest (SDI 0.900 ± 0.059). As resuscitation efforts continued and time from initial arrest increased, the scanner’s performance decreased dramatically (SDI 0.597 ± 0.241 in late arrest). Conclusion An automated ultrasound device (bladder scanner) reliably traced porcine hearts during cardiac arrest. It is possible a device could be developed to indicate where compressions should be performed without requiring the operator to interpret ultrasound images. Further investigation into rapid, automated, sonographic localization of the heart to identify the area of compression in out-of-hospital cardiac arrest is warranted.


2021 ◽  
Vol 907 (1) ◽  
pp. 012002
Author(s):  
Livian Teddy ◽  
Husnul Hidayat ◽  
Dessa Andriyali A

Abstract In Indonesia, an earthquake-prone area, building designs must be earthquake resistant, and using shear walls is one of the ways to make buildings more earthquake resistant. However, determining the requirements and optimal position of shear walls is difficult. Miscalculating in their positioning can cause torsion and other unpredictable behavior. Previous studies were done to know shear walls’ optimal areas and positioning. The first way was trial and error, but this method was ineffective and took a long time. The second way, MATLAB programming, is actually very effective since the needs and orientation of the walls can be determined precisely. Nevertheless, not all structural engineers and architects master the programming language. This study, therefore, proposes relatively simple formulas and procedures to determine the optimal area and positioning of shear walls for architects preliminary design during architecture design process. The accuracy test for the formulas and procedures was carried out using ETABS simulation experiments on 10 building models with various irregular categories. The result showed the formulas and procedures proposed in this study were quite accurate in calculating the needs and position of shear walls. Optimal conditions, furthermore, were quite easy to achieve in symmetrical geometric compositions (1 or 2 axes) while organic or random geometric compositions were quite difficult to achieve. When the use of shear walls achieves optimal condition, the strength and stiffness of a building are increased, and the distribution of its strength and stiffness is relatively even, hence anticipating deformation behavior and reducing building eccentricity.


2021 ◽  
Author(s):  
Shumpei Hisamoto ◽  
Koichi Goka ◽  
Yoshiko Sakamoto

Abstract Efforts to eradicate invasive alien species commonly use simulations to calculate the cost-effectiveness of surveys. Although eradication of Solenopsis invicta in the early stages of an invasion is important, few simulations are available to calculate the cost-effectiveness of surveys when a single colony has been detected. In the case of S. invicta, it is difficult to determine from the status of the detected colony whether new queens have dispersed, so it is necessary to consider dispersal as a probabilistic event and calculate its probability. We therefore first constructed a mathematical model in which we used Bayesian statistics to estimate the probability of dispersal as a function of the results of the survey. This mathematical model revealed that the efficacy of the survey and the associated cost differed greatly between cases depending on whether dispersal was or was not confirmed. Next, we developed a simulation that incorporated this mathematical model to inform the determination of the survey area when a single colony had been detected. The simulation showed how ecological parameters and geographical information could be used to identify an efficacious survey area, even in heterogeneous landscapes such as international ports where invasions occur sporadically. Finally, we used this simulation to assess the efficacy of a survey in the case of an S. invicta outbreak at the Port of Tokyo, Japan. The results suggested that the survey covered a sufficiently wide area but that it could have been designed in a more efficacious manner.


2021 ◽  
pp. 1-10
Author(s):  
Demetrios Lefas ◽  
Robert Miller

Abstract Every supersonic fan/compressor blade row has a streamtube, the ‘sonic streamtube’, which operates with a blade relative inlet Mach number of one. A key parameter in the design of the ‘sonic streamtube’ is the area ratio between the blade throat area and upstream passage area, Athroat/Ainlet. In this paper, it is shown that one unique value exists for this area ratio. If the area ratio differs, even slightly, from this unique value then the blade either chokes or has its suction surface boundary layer separated due to a strong shock. It is therefore surprising that in practice designers have relatively little problem designing blade sections with an inlet relative Mach number close to unity. This paper shows that this occurs due to a physical mechanism known as ‘transonic relief’. If a designer makes a mistake and designs a blade with a ‘sonic streamtube’ which has the wrong area ratio, then ‘transonic relief’, will self-adjust the spanwise streamtube height automatically moving it towards the unique optimal area ratio, correcting for the designer's error. Furthermore, as the blade incidence changes, the spanwise streamtube height self-adjusts, moving the area ratio towards its unique optimal value. Without ‘transonic relief’, supersonic or transonic fan/compressor design would be impossible. The paper develops a simple model which allows ‘transonic relief’ to be decoupled from other mechanisms, and to be systematically studied. The physical mechanism on which it is based is thus determined and its implications for blade design and manufacturing discussed.


2021 ◽  
Vol 10 (10) ◽  
pp. e212101018841
Author(s):  
Julio Leite Azancort Neto ◽  
Arleson Lui Silva Gonçalves ◽  
Brennus Caio Carvalho da Cruz ◽  
Larissa Luz Gomes ◽  
Denis Carlos Lima Costa

The several papers recently published, applied to sustainable development, has been considering new methodologies and techniques in identifying the main criteria, in numeric format, that are useful in formulating possible solutions to the solid waste problem. This paper presents the Mathematical and Computational Modeling Process (PM2C), applied in the determination of control variables related to selection of areas destined to the construction of landfills, in order to benefit from new analyzes and values obtained by methods such as AHP (Analytical Hierarchy Process) and GIS (Geographic Information Systems). The main objective of this paper is the use of Artificial Intelligence (AI), through a Decision Tree strategy, as a selective method and optimal solutions in choosing the best area dedicated to the construction of landfills, with the creation and analysis of new values applied to scenarios defined in the paper of Andrade e Barbosa (2015). The results, expressed in analytical and graphical forms, show the individual values for each criterion and new scenarios involved in the phenomena. This paper highlights the importance of incorporating new conditions and criteria to propose a new decision-making rule, simultaneously, associating qualitative and quantitative characteristics, related to social and economic effects, applied to the environment management system. Based on these principles, it was possible to simulate new scenarios that demonstrate, with very high precision, the best values of useful criteria for decision-making in the selection of the optimal area for implementation of a landfill.


2021 ◽  
Vol 1038 ◽  
pp. 193-202
Author(s):  
Sergii G. Guzii ◽  
Tetiana Kurska ◽  
Volodymyr Andronov ◽  
Mykola Adamenko

The influence of the main structure-forming oxides Li2O/Al2O3, SiO2/Al2O3 and H2O/Al2O3 on the physical, rheological and colloidal-chemical properties of lithium-containing alumosilicate suspensions xLi2O-Al2O3-nSiO2-mH2O in the system are presented for the first time. As a result of optimization, the optimal area of influence of variable factors was determined for the ratio of oxides Li2O/Al2O3 from 0.82 to 1.05 mol, SiO2/Al2O3 from 3.4 to 4.5 mol and H2O/Al2O3 from 19 to 21.5 mol, providing normative levels of properties of lithium-containing alumosilicate suspensions, namely: density from 1.4 to 1.521 g/cm3, process viscosity from 15 to 47 sec, pH from 11.15 to 11.34, surface tension from 51.4 to 60.4 mN/m, cosine of the substrate contact angle from 0, 57 to 0.91, work of adhesion forces from 97 to 116 mN/m, work of cohesion forces from 103 to 121 mN/m, work of wetting forces from 27 to 52 mN/m, wetting coefficient from 0.78 to 0.96, spreading coefficient from –5 to –20 mN/m. The data obtained will form the basis for the creation of protective materials of new generation that, in the event of emergencies, can provide both the protection of people and technological equipment, buildings and constructions.


2021 ◽  
Vol 82 (1) ◽  
pp. 47-57 ◽  
Author(s):  
Anis Davoudi ◽  
Catherine Dion ◽  
Shawna Amini ◽  
Patrick J. Tighe ◽  
Catherine C. Price ◽  
...  

Background: Advantages of digital clock drawing metrics for dementia subtype classification needs examination. Objective: To assess how well kinematic, time-based, and visuospatial features extracted from the digital Clock Drawing Test (dCDT) can classify a combined group of Alzheimer’s disease/Vascular Dementia patients versus healthy controls (HC), and classify dementia patients with Alzheimer’s disease (AD) versus vascular dementia (VaD). Methods: Healthy, community-dwelling control participants (n = 175), patients diagnosed clinically with Alzheimer’s disease (n = 29), and vascular dementia (n = 27) completed the dCDT to command and copy clock drawing conditions. Thirty-seven dCDT command and 37 copy dCDT features were extracted and used with Random Forest classification models. Results: When HC participants were compared to participants with dementia, optimal area under the curve was achieved using models that combined both command and copy dCDT features (AUC = 91.52%). Similarly, when AD versus VaD participants were compared, optimal area under the curve was, achieved with models that combined both command and copy features (AUC = 76.94%). Subsequent follow-up analyses of a corpus of 10 variables of interest determined using a Gini Index found that groups could be dissociated based on kinematic, time-based, and visuospatial features. Conclusion: The dCDT is able to operationally define graphomotor output that cannot be measured using traditional paper and pencil test administration in older health controls and participants with dementia. These data suggest that kinematic, time-based, and visuospatial behavior obtained using the dCDT may provide additional neurocognitive biomarkers that may be able to identify and tract dementia syndromes.


2021 ◽  
Author(s):  
Jonathan Casey

Abstract This study explores the opportunities for interlinkages across national planning processes for invasive species management (ISM), national climate change adaptation plans (NAPs), national biodiversity management plans (NBSAPs), and other related policies. Focusing on four countries - Pakistan, Zambia, Kenya, and Ghana - the paper aims to identify policy recommendations for more integrated approaches and to achieve greater efficiency in resource allocation and spending. It finds that there is currently very little integration between these policy areas, and little overlap in implementation systems. It identifies sub-national planning and governance systems as an optimal area for increased harmonization of policy and practice to facilitate locally-led climate adaptation and area-specific responses to ISM issues.


Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2482
Author(s):  
Youkyung Hong ◽  
Sunggoo Jung ◽  
Suseong Kim ◽  
Jihun Cha

This study proposes an entire hardware and software architecture from operator input to motor command for the autonomous area coverage mission using multiple unmanned aerial vehicles. Despite the rapid growth of commercial drone services, there are many limitations on operations, such as a low decision-making autonomy and the need for experienced operators to intervene in the whole process. For performing the area coverage mission more efficiently and autonomously, this study newly designs an optimization problem that allocates waypoints created to cover that area to unmanned aerial vehicles. With an optimized list of waypoints, unmanned aerial vehicles can fill the given areas with their footprints in a minimal amount of time and do not overlap each other during the mission. In addition, this study performs both various simulations for quantitative analysis and an outdoor experiment through real hardware implementation in order to verify the performance sufficiently. The methodologies developed in this study could be applied to endless applications using unmanned aerial vehicles equipped with mission-specific sensors.


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