scholarly journals Multivariate sea storm hindcasting and design: the isotropic buoy-ungauged generator procedure

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Gianfausto Salvadori ◽  
Giuseppe Roberto Tomasicchio ◽  
Felice D’Alessandro ◽  
Letizia Lusito ◽  
Antonio Francone
Keyword(s):  
Target Location ◽  
Wave Climate ◽  
Geographical Information ◽  
Independent Random Variables ◽  
Target Area ◽  
Ungauged Sites ◽  
Critical Issues ◽  
Set Up ◽  
Generation Mechanisms ◽  
Sea Storm

AbstractThe present work provides indications for assessment of wave climate and design of structures at sea at ungauged sites, both critical issues in Ocean sciences. The paper is of methodological nature and of global worldwide applicability. It shows how suitable wave hindcasting relations can be exploited in order to provide sea storm scenarios at an ungauged (Target) location useful for design purposes: in particular, only geographical information and the knowledge of another gauged (Source) buoy are used. Several are the novelties introduced. (i) New hindcasting relations are derived. (ii) A full statistical model is set up for the Target area, whereas traditional hindcasting simply transfers time series from a gauged to an ungauged site: this gives the possibility to appropriately deal with design and hazard assessment at the Target location. (iii) The multivariate behavior of non-independent random variables is properly modelled by using the Theory of Copulas. As an illustration, a number of case studies is investigated, involving four pairs of buoys which, given their positions and exposures, are representative of a wide variety of sea states and conditions, as well as of different wave generation mechanisms.

scholarly journals Physics-Informed Modeling and Control of Multi-Actuator Soft Catheter Robots

2022 ◽  
Vol 8 ◽  
Author(s):  
Seyede Fatemeh Ghoreishi ◽  
Ryan D. Sochol ◽  
Dheeraj Gandhi ◽  
Axel Krieger ◽  
Mark Fuge
Keyword(s):  
Target Location ◽  
Target Area ◽  
Target Vessel ◽  
Modeling And Control ◽  
Small Vessels ◽  
Fixed Design ◽  
Dependent Model ◽  
Pass Through ◽  
Multiple Actuators ◽  
And Control

Catheter-based endovascular interventional procedures have become increasingly popular in recent years as they are less invasive and patients spend less time in the hospital with less recovery time and less pain. These advantages have led to a significant growth in the number of procedures that are performed annually. However, it is still challenging to position a catheter in a target vessel branch within the highly complicated and delicate vascular structure. In fact, vessel tortuosity and angulation, which cause difficulties in catheterization and reaching the target site, have been reported as the main causes of failure in endovascular procedures. Maneuverability of a catheter for intravascular navigation is a key to reaching the target area; ability of a catheter to move within the target vessel during trajectory tracking thus affects to a great extent the length and success of the procedure. To address this issue, this paper models soft catheter robots with multiple actuators and provides a time-dependent model for characterizing the dynamics of multi-actuator soft catheter robots. Built on this model, an efficient and scalable optimization-based framework is developed for guiding the catheter to pass through arteries and reach the target where an aneurysm is located. The proposed framework models the deflection of the multi-actuator soft catheter robot and develops a control strategy for movement of catheter along a desired trajectory. This provides a simulation-based framework for selection of catheters prior to endovascular catheterization procedures, assuring that given a fixed design, the catheter is able to reach the target location. The results demonstrate the benefits that can be achieved by design and control of catheters with multiple number of actuators for navigation into small vessels.

Structural Analysis of a Gas Turbine Axial Compressor Blade Eroded by Online Water Washing

2020 ◽  
Author(s):  
Rossella Cinelli ◽  
Gianluca Maggiani ◽  
Serena Gabriele ◽  
Alessio Castorrini ◽  
Giuliano Agati ◽  
...  
Keyword(s):  
Structural Analysis ◽  
Gas Turbine ◽  
Axial Compressor ◽  
Compressor Blades ◽  
Performance Levels ◽  
Water Washing ◽  
Critical Issues ◽  
Air Intake ◽  
Set Up ◽  
The Impact

Abstract The Gas Turbine (GT) Axial Compressor (AXCO) can absorb up to the 30% of the power produced by the GT, being the component with the largest impact over the performances. The axial compressor blades might undergo the fouling phenomena as a consequence of the unwanted material locally accumulating during the machine operations. The presence of such polluting substances reduces the aerodynamic efficiency as well as the air intake causing the drop of performances and the increase of the fuel consumption. To address the above-mentioned critical issues, several washing strategies have been implemented so far, among the most promising ones, High Flow On-Line Water Washing (HFOLWW) is worth to mention. Exploiting this technique, the performance levels are preserved, whereas the stops for maintenance should be reduced. Nevertheless, this comes at the cost of a long-term erosion exposure caused by the impact of water washing droplets. Hence, it was deemed necessary to carry out a finite element method (FEM) structural analysis of the first rotor stage of the compressor of an aeroderivative GT, integrated into the HFOLWW scheme, in order to evaluate the fatigue strength of the component subjected to the erosion; possibly along with its acceptability limits. The first step requires the determination of the blade areas affected by erosion, using computational fluid dynamics (CFD) simulations, followed by the creation and the 3D modelling of the damaged geometry. The final step consists in the evaluation of the static stress and the dynamic agents, to perform a fatigue analysis through the Goodman relation and carrying out a simulation of damage propagation exploiting the theory of fracture mechanics. This procedure has been extended to the damage-free baseline component to set-up a model suitable for comparison. The structural analysis confirms the design of the blade, moreover dynamic and static evaluation of the eroded profiles haven’t outlined any working, nor mechanical, issue. This entitles the structural choice of HFOLWW as a system which guarantees full performance levels of the compressor.

I bambini e l'aerosol. Studio per valutare la compliance della terapia aerosolica associata all'uso di un computer didattico in bambini in etŕ scolastica

2009 ◽  
pp. 91-106
Author(s):  
Roberto Cerabolini ◽  
Gabrielle Boissard ◽  
Tiziana Buonfiglio ◽  
Maria Pia Savorelli
Keyword(s):  
Focus Groups ◽  
Educational Games ◽  
Aerosol Therapy ◽  
Clinical Interviews ◽  
Children Behavior ◽  
Experimental Environment ◽  
Children And Parents ◽  
Starting Point ◽  
Critical Issues ◽  
Set Up

- A study has been carried out in order to evaluate the possibility of overcoming children aversion to aerosol therapy as well as facilitating their parents' task. Starting point of this study was the investigation, which was performed through focus groups, clinical interviews and a playful approach, on how children and parents perceive the aerosol therapy. After having identified critical issues and spontaneous proposals to ameliorate aerosol administration, the Authors evaluated the results obtained by the association of the traditional aerosol therapy with a device equipped with educational games. An experimental environment was set up in a school together with a procedure aiming at evaluating the children behavior towards aerosol therapy administered with and without the device equipped with educational games. The results of this monocentric, randomized, cross-over study demonstrated a statistically significant increase of the compliance index when aerosol therapy was administered with the device equipped with educational games, increasing interest, satisfaction and pleasure during the aerosol administration, which was accepted for a longer time.

Technical and Economical Feasibility of Biomass Use for Power Generation in Sicily

2012 ◽  
Vol 3 (1) ◽  
pp. 40-50 ◽  
Author(s):  
Antonio Messineo ◽  
Domenico Panno ◽  
Roberto Volpe
Keyword(s):  
Power Plant ◽  
Sustainable Management ◽  
Power Plants ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Geographical Information ◽  
Critical Issues ◽  
Economical Feasibility ◽  
Choice Of Technology

Biomass can provide a reliable support for production of biofuels while contributing to sustainable management of natural resources. Many countries, including Italy, have introduced important incentive schemes to support the use of biomass for electricity, heat and transportation. This has raised considerable interest towards the use of biomass for energy generation purposes. Nonetheless, the design and installation of biomass-fuelled power plants present several critical issues, such as choice and availability of biomass, choice of technology, power plant localization and logistics. The case study tackled in this paper evaluates the economies originated by a 1MWel Organic Rankine Cycle (ORC) turbine coupled with a biomass fuelled boiler, installed in an area close to Palermo (Italy). A Geographical Information System (GIS) was used to localize the power plant and to optimize logistics. The thermodynamics of the plant as a whole were also analyzed. Finally, two different scenarios were simulated for project financial evaluation.

Pediatric blinatumomab preparation: Risk assessment on SmPC for software compliance

2020 ◽  
pp. 107815522096639
Author(s):  
Mario Cirino ◽  
Riccardo Provasi ◽  
Irina Cebulec ◽  
Clara Palmieri ◽  
Paolo Schincariol ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Poor Prognosis ◽  
Computer Processing ◽  
Second Phase ◽  
Preparation Process ◽  
Critical Issues ◽  
Adults And Children ◽  
Two Phases ◽  
Set Up ◽  
Cancer In Children

Introduction Blinatumomab is an anticancer drug used in the treatment of Acute Lymphoblastic Leukaemia (ALL) in both adults and children. ALL is the most common form of cancer in children and patients who are refractory to standard treatments have poor prognosis. The preparation of blinatumomab is unique and extremely complex. It’s important to carry out any information to identify all the critical issues related to the preparation of blinatumomab: sharing procedure between prescribers, staff of the Centralized Chemotherapy Preparation Unit [Unità Farmaci Antiblastici (UFA)] and administering nurses aimed at reducing the clinical risk related to the management of the drug blinatumomab and to obtain correct prescriptions on the real dose to be prepared, safe worksheets with computer processing of all variables (volumes to be added and corresponding dose of drug) and complete labels containing all the information necessary for the control of the preparation and its correct infusion. Methods A computerized process involves the use of specific software to which precise instructions must be given. This study is divided into two phases, the first one focused on the analysis of Summary of Product Characteristics (SmPC) and the extrapolation of any unclear part of SmPC. The second phase involved the manufacturer to answer a questionnaire. Results This comparison with the company allowed to perfect the blinatumomab preparation process leading to: 1. allow the patient to be discharged and return a few times for infusions and consequently reduce the number of medical prescriptions; 2. set up the drug for each patient every 4 days; 3. reduce costs related to devices, staff employed. Conclusion Computerizing the preparation of anti-blastic drugs is a necessary path for the safety of the patient and all the operators involved, however it may be necessary to make changes in the preparation process to allow the software to work correctly. The comparison between pharmacist, clinician and, where necessary, the manufacturer of the drug, was effective in the preparation of this drug.

scholarly journals Mobility-Aware Service Caching in Mobile Edge Computing for Internet of Things

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 610 ◽  
Author(s):  
Hua Wei ◽  
Hong Luo ◽  
Yan Sun
Keyword(s):  
Target Location ◽  
Geometric Model ◽  
Back Propagation ◽  
Base Station ◽  
Edge Computing ◽  
Computation Offloading ◽  
Target Area ◽  
Mobile Edge Computing ◽  
Trajectory Data ◽  
Practical Applications

The mobile edge computing architecture successfully solves the problem of high latency in cloud computing. However, current research focuses on computation offloading and lacks research on service caching issues. To solve the service caching problem, especially for scenarios with high mobility in the Sensor Networks environment, we study the mobility-aware service caching mechanism. Our goal is to maximize the number of users who are served by the local edge-cloud, and we need to make predictions about the user’s target location to avoid invalid service requests. First, we propose an idealized geometric model to predict the target area of a user’s movement. Since it is difficult to obtain all the data needed by the model in practical applications, we use frequent patterns to mine local moving track information. Then, by using the results of the trajectory data mining and the proposed geometric model, we make predictions about the user’s target location. Based on the prediction result and existing service cache, the service request is forwarded to the appropriate base station through the service allocation algorithm. Finally, to be able to train and predict the most popular services online, we propose a service cache selection algorithm based on back-propagation (BP) neural network. The simulation experiments show that our service cache algorithm reduces the service response time by about 13.21% on average compared to other algorithms, and increases the local service proportion by about 15.19% on average compared to the algorithm without mobility prediction.

Modelling Wave Energy Resources in the Irish West Coast

2011 ◽  
Author(s):  
A. Rute Bento ◽  
Paulo Martinho ◽  
Ricardo Campos ◽  
C. Guedes Soares
Keyword(s):  
Wave Energy ◽  
West Coast ◽  
Wave Climate ◽  
Extensive Study ◽  
Wave Power ◽  
Target Area ◽  
Wave Models ◽  
The Time Domain ◽  
Validation Tests ◽  
Buoy Data

In order to assess the potential wave energy extraction, a study is made to validate a model that can be used to characterize Ireland’s wave climate in a more extensive study. The target area is the Irish West Coast, known for having the highest average wave power in Europe. The wave conditions in the coastal area were characterized by coupling the wave models SWAN and WAVEWATCH III. Validation tests are carried out with buoy data so that the model’s performance can be evaluated. The wave parameters considered for the comparisons in the time domain are significant wave height and mean period, and the spatial distribution of wave energy is examined in a case study. Theoretical values of wave power are obtained for sites close to the coast and in particular for the two tests sites of Galway and Belmullet.

scholarly journals Comparison of Transcranial Direct Current Stimulation Electrode Montages for the Lower Limb Motor Cortex

2019 ◽  
Vol 9 (8) ◽  
pp. 189 ◽  
Author(s):  
Radhika Patel ◽  
Sangeetha Madhavan
Keyword(s):  
Motor Control ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Lower Limb ◽  
Target Location ◽  
Motor Behavior ◽  
Tibialis Anterior Muscle ◽  
Target Area ◽  
Corticomotor Excitability ◽  
Direct Current Stimulation

Transcranial direct current stimulation (tDCS) has been widely explored as a neuromodulatory adjunct to modulate corticomotor excitability and improve motor behavior. However, issues with the effectiveness of tDCS have led to the exploration of empirical and experimental alternate electrode placements to enhance neuromodulatory effects. Here, we conducted a preliminary study to compare a novel electrode montage (which involved placing 13 cm2 electrodes anterior and posterior to the target location) to the traditionally used electrode montage (13 cm2 stimulating electrode over the target area and the 35 cm2 reference electrode over the contralateral orbit). We examined the effects of tDCS of the lower limb motor area (M1) by measuring the corticomotor excitability (CME) of the tibialis anterior muscle using transcranial magnetic stimulation in twenty healthy participants. We examined behavioral effects using a skilled motor control task performed with the ankle. We did not find one electrode montage to be superior to the other for changes in the CME or motor control. When the group was dichotomized into responders and non-responders (based on upregulation in CME), we found that the responders showed significant upregulation from baseline after tDCS for both montages. However, only the responders in the traditional montage group showed significant changes in motor control after tDCS. These results do not support the superiority of the new anterior–posterior montage over the traditional montage. Further work with a larger cohort and multiple cumulative sessions may be necessary to confirm our results.

scholarly journals Return- and hitting-time distributions of small sets in infinite measure preserving systems

2019 ◽  
Vol 40 (8) ◽  
pp. 2239-2273
Author(s):  
SIMON RECHBERGER ◽  
ROLAND ZWEIMÜLLER
Keyword(s):  
Sufficient Conditions ◽  
Finite Measure ◽  
Hitting Time ◽  
Independent Random Variables ◽  
Limit Laws ◽  
Interval Maps ◽  
Infinite Measure ◽  
Sufficient Conditions For Convergence ◽  
Set Up ◽  
The One

We study convergence of return- and hitting-time distributions of small sets $E_{k}$ with $\unicode[STIX]{x1D707}(E_{k})\rightarrow 0$ in recurrent ergodic dynamical systems preserving an infinite measure $\unicode[STIX]{x1D707}$. Some properties which are easy in finite measure situations break down in this null-recurrent set-up. However, in the presence of a uniform set $Y$ with wandering rate regularly varying of index $1-\unicode[STIX]{x1D6FC}$ with $\unicode[STIX]{x1D6FC}\in (0,1]$, there is a scaling function suitable for all subsets of $Y$. In this case, we show that return distributions for the $E_{k}$ converge if and only if the corresponding hitting-time distributions do, and we derive an explicit relation between the two limit laws. Some consequences of this result are discussed. In particular, this leads to improved sufficient conditions for convergence to ${\mathcal{E}}^{1/\unicode[STIX]{x1D6FC}}{\mathcal{G}}_{\unicode[STIX]{x1D6FC}}$, where ${\mathcal{E}}$ and ${\mathcal{G}}_{\unicode[STIX]{x1D6FC}}$ are independent random variables, with ${\mathcal{E}}$ exponentially distributed and ${\mathcal{G}}_{\unicode[STIX]{x1D6FC}}$ following the one-sided stable law of order $\unicode[STIX]{x1D6FC}$ (and ${\mathcal{G}}_{1}:=1$). The same principle also reveals the limit laws (different from the above) which occur at hyperbolic periodic points of prototypical null-recurrent interval maps. We also derive similar results for the barely recurrent $\unicode[STIX]{x1D6FC}=0$ case.

Under the ice and over the sky – aspects of building the International Quaternary Map of Europe and potentially useful parallels to planetary geological map projects

2020 ◽  
Author(s):  
Kristine Asch ◽  
Andrea Naß ◽  
Stephan van Gasselt
Keyword(s):  
Land Surface ◽  
Active Faults ◽  
Geological Mapping ◽  
Geographical Information ◽  
Current Status ◽  
Small Scale ◽  
Scientific Quality ◽  
European Continent ◽  
Geological Map ◽  
Set Up

<p>The project of the International Quaternary Map of Europe project (IQUAME 2500) is a major international initiative coordinated by BGR under the auspices of the CGMW (Commission of the Geological Map of the Word, Sub-Commission Europe) and with support of INQUA (International Union for Quaternary Research). It started in 2011 at the INQUA congress in Bern and aims to show the distribution of Quaternary features at the land surface and general marine deposits across the entire European continent. The map is planned as web-based geographical information system (GIS) and is going to include the Quaternary on- and off-shore information on e.g. glaciogenic elements, geomorphologic features, age and lithology of Quaternary units, last extent of ice sheets (Weichselian, Saalian, if possible Elsterian), faults, active faults off-shore Quaternary information (in cooperation with the European Union EMODnet Geology project) and more.</p><p>Partner institutions from more than 30 countries including geological survey organisations from Russia in the East, Portugal in the West, Norway in the North and Cyprus in the South are participating; a scientific board of Quaternary researchers ensures the high scientific quality of resulting map. For a multinational and cross-boundary project like this, international collaboration is the key to success. This project requires that data originally set up in a plethora of regional and national classifications need to be adapted, integrated and harmonized in respect to semantics, structure and geometry. To achieve this aim common rules needed to used such as those defined by the European INSPIRE Directive or be set up and applied by all participants:  structured vocabularies (incl. definitions of terms) to describe the above contents, cartographic guidelines to suite the scale and last but not least generally applicable tools to aid the partners to submit their data to the project.</p><p>Ultimately, the aim is to create an pan-European, internationally harmonized, comprehensive, spatial geological database where relevant properties of the Quaternary layers can be retrieved, combined, selected and cross-referenced across political boundaries and also to provide a summary of the current status of European Quaternary geological research.</p><p>Looking at planetary mapping, e.g. of Mars and Moon, there are several similarities. The surfaces of terrestrial planets are shaped by geologic processes that are similar to those operating on Earth, therefore endogenic and exogenic landforms (such as lava flows, glacial deposits, and impact craters) are regularly mapped by the scientific community.  Beside specific scientific mapping projects conducted by individual researchers and groups different organisations and institutes are producing planetary maps, such as NASA, ESA, ROSCOSMOS and MIIGAiK (Russia), USGS (USA), CAS/NOAC/SGCAS/RADI (China), DLR (Germany), or the British Ordnance Survey. This presentation aims to introduce the small-scale Quaternary mapping of one part of planet Earth, i.e. Europe, to present its collaborative aspects, to highlight the parallels to planetary mapping and to suggest potentially useful aspects for planetary geological mapping projects.</p>

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